DIY_EFI Digest Tuesday, 6 February 1996 Volume 01 : Number 033 In this issue: Re[2]: IAC Re: Still more Questions .... Re: IAC Re: Bosch Mono-Jetronic Re: Still more Questions .... DIY_EFI Vendor List - Revised DIY_EFI Vendor List - Revised DIY_EFI Vendor List - Revised RE: Ford MAF sensor Re: Spellcheckers Engine codes; PC to General Motors ALDL interface RE: re: Re: Sensor Questions? Re: IAC fwd: What about H202 Re: IAC RE: re: Re: Sensor Questions? Electronic thottles See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: dzorde@xxx.au Date: Mon, 05 Feb 96 16:36:48 Subject: Re[2]: IAC I'm using a Wolf 3D system which doesn't allow for control of the standard IAC, thus I was thinking of either using: 1. the old style solenoid switch that opens the throttle a bit when power is applied. Requires the original IAC mounting hole to be blocked off. 2. a temperature sensing bi-metal type air by-pass valve as used on many Nissans. Requires blocking of the original IAC mounting hole also. 3. Nothing at all. Dan dzorde@xxx.au ______________________________ Reply Separator _________________________________ Subject: Re: IAC Author: diy_efi@xxx.edu at INTERNET Date: 05/2/96 4:25 PM You wrote: > > > > On the subject of the GM IAC(idle air controller) for the TPI engines. > Does anyone know of a replacement, working of sensing the temperature > or similar, ie. some sort of bi-metal spring system. The problem is > that I need some sort of idle stabilisation on a TPI system but the > ECU does not allow for control of the standard IAC. > > Is it possible to leave the IAC off all together? > > Any ideas will be appreciated. Preferably the parts should be > available of Australian cars, since US parts are to expensive over > here. > > > Dan dzorde@xxx.au > > the iac is just a little stepping motor gm bottoms it shut at start and then backs it off a a certain number of steps to control idle mixture air and also as a deceleration valve during throttle release closing. what sort of ecm are you using? ford uses a solonoid thats pwm to do the same thing but ive heard the gm stepper works better and smother as long as the valve lead screw is kept clean (i own a iac gm ). maybe i could design a little gaget using a pic16 up. ------------------------------ From: atsakiri@xxx.com Date: Mon, 05 Feb 96 08:57:59 -0500 Subject: Re: Still more Questions .... > I have more question on MAF sensors > > The MAF on OEM's is always plaed very fare from the throtle body > by doing this we have to > reaslise that we have the intake + the air hose that act as a > resevoir after the metered > air has passed the MAF, would it not be better placed as close > as posible to the intake > ??? The "reservoir" problem is definitely a disadvantage of placing a mass air flow sensor considerably upstream of the intake valves. However, there are advantages of this placement too. The sensing element is usually small compared to the full diameter of the sensor. A relationship between the local flow and the bulk flow is necessary. The more well-developed the flow is, the more accurate and robust such a relationship will be. Also, the flow is not steady, but pulsating. The flow rate varies due to the cyclic nature of the engine's induction. Placing a sensor upstream helps to isolate it from the pulsations. Anthony Tsakiris - --------------------------------------------------------------------------- The opinions expressed are my own and not necessarily those of my employer. ------------------------------ From: Paul Beam Date: Mon, 5 Feb 1996 09:44:19 -0500 Subject: Re: IAC At 08:18 AM 2/5/96, you wrote: > Is it possible to leave the IAC off all together? You could probably do that, but it might not idle well in cold weather or with the A/C on. You would just have to let enough air into the system so that it will idle under all conditions. If you have any kind of solenoid valve, you could use that to let more air in when the weather is cold or accessories are on. You can let air in anywhere in the intake -- even a vacuum line. It's a miracle their are more problems with "unintended acceleration" due to a vacuum leak. Some other manufacturers use a pulse width modulated solenoid to do the same function. Hope this helps, Paul R Paul Beam Computer Systems Engineer Johnson Bible College 7900 Johnson Drive Knoxville, TN 37998 (423) 573-4517 (423) 579-2337 fax ------------------------------ From: Wayne Braun Date: Mon, 05 Feb 1996 08:53:10 -0600 Subject: Re: Bosch Mono-Jetronic At 09:38 AM 2/5/96 GMT+0200, you wrote: >>So Land Shark a.k.a. Jim sez: > >>>Actually, the Uno is remarkably driveable. Handles _really_ well. Never had >>>any problems at all, except this flat spot that crept in recently. >> >> OK, well .. let's fix that flatspot ... Have you checked the throttlepot?? >> >Now here lies the crunch. The manual I have sez "don't remove that pot, it's >factory adjusted". I can't get a new pot, or even a new pot attached to a >throttle body (Which I would need if the thing is factory adjusted). I'll >have to buy the whole thing, including idle servo and injector. Now I'm sure >that'll fix the flat spot, but I can get a carburettor for a third of the >price. Lessee, R8000 = 200 cases of beer, what can _you_ buy for the >equivalent of 200 cases of beer? Probably a new car :-) > >So if I remove the pot and bugger up the adjustment, I'm f*--ed. So now I'm >trying to figure out whether that is the culprit. If I open the thing and >find that the pot's OK, and then can't get it back together again, Hooo Boy, >probably kill myself :-) > > >Wouter >-- >Wouter de Waal Phone : +27 21 683 5490 >Development Engineer Fax : +27 21 683 5435 >CCII Systems >Kenilworth, South Africa > > That doesn't sound very good at all. The throttle position sensor ( TPS ) is almost an annual replacement item for me. Severe weather will do that sort of thing but also the TPS in the Nissan Sentra ( Throttle body injection ) is a rather poor design. I took one apart and you can easily see the throttle position for the speeds you normally drive. Just look for the dips in the track where it is worn out. It usually takes me longer to convince the dealer whats wrong that for them to fix it. Wayne Braun Wayne Braun Product Support Develcon Electronics Email: Wayne.Braun@xxx.com Phone: (306) 933-3300 or 1-800-667-9333 FAX: (306)978-8860 ------------------------------ From: "Mark Hillier" Date: Mon, 5 Feb 1996 10:04:56 +0000 Subject: Re: Still more Questions .... > >I have more question on MAF sensors > > > >The MAF on OEM's is always plaed very fare from the throtle body by doing > this we have to > >reaslise that we have the intake + the air hose that act as a resevoir > after the metered > >air has passed the MAF, would it not be better placed as close as posible > to the intake > >??? > >And also why not just put it after the T-Body and calculate the real air > density, since > >usulay wy have coulant heating the the T-Body. > > > >And just to srew things around on super/torbo charged engins the T-Body is > after the > >compressor by placing it there we have to add a bypass valve on the > intaketo reduce the > >chance of over boost when the trotle plates close sudenly. > >By putting the T-Body beafore the compressor we do not nead the bypass > valve but the > >compressor must have sealedbearing shafts to keep from sucking the oil from > them when the > >intake is at a vacum, Would there be any other ploblems ???? > > > > > >//---------------------------------------------------------------------------- > >// Marchil@xxx.NET > >// Alain Marchildon > >// 1271 Bernard West > >// Outremont, Quebec Canada > >// H2V 1V8 > > > Do they have spell checkers up there? > > Peter Wales > President Superchips Inc > Chairman Superchips Ltd "Timing is everything" > Superchips home page with all the answers http://www.superchips.com > Peter, with all due respect, one of the biggest problems the U.S. has is that it is blisfully ignorant of other cultures. English is not the only language spoken in the world. In fact, I believe it is *third*. A quick look at this guy's name and location will tell you that this guy's mother tongue is French. If you spoke French you would understand why he spells like that in English. I thinks he did quite well....you understood what he was trying to say -right ? How about some slack ? Mark Hillier mhillier@xxx.com Montreal, Canada ------------------------------ From: orin@xxx. Harding) Date: Mon, 05 Feb 1996 10:22:49 -0500 Subject: DIY_EFI Vendor List - Revised Revised #8 and added #10 After Market DIY_EFI Systems: (BASE system prices shown. Usually doesn't include sensors) 1. Electromotive, Inc. 14004-J Willard Road Chantilly, VA. 22021 (703) 378-2444 All prices ECU only a. HPV-1 Direct fire, Distributorless Ignition US$439 (4 Cyl) b. HPV-3B " " " " US$664 (4 Cyl) c. TEC-I Engine Management (Fuel and IgnManagement)US$1,500 (6 Cyl) d. TEC-II " " " " " " US$999 (4 Cyl) e. Software for the above US$150 - 550 2. Haltech (Australia) US Distributor Performance Automotive Electronics 2158 W. Northwest Highway, Suite 400 Dallas, TX 75220 (214) 831-9800 All prices ECU only a. IG4 Ignition Control US$480 b. F7B EFI system US$640 c. F7C EFI system US$680 d. F9 EFI system US$680 e. E6 EFI system US$960 2a. EFI (Haltech) Unit 7 130 Taren Point Road Taren Point 2229 Sydney Australia 3. Mr. Gasket 8700 Brookpark Rd. Cleveland, OH 44129 (216) 398-8300 Contact Mark Hamel (X488) 3a. ACCEL - Same address and phone 3b. Digital Fuel Injection (DFI)- Owned by Mr. Gasket 37732 Hills Tech Dr. Farmington Hills, MI 48024 a. 74040A Universal US$740 b. 74022L (Chev 350) US$900 c. Calmap software US$185 4. Emtech (Australia) 5. NOS/EFI Tech. 6. Holley 11955 E. Nine Mile Road Warren, MI 48089-2003 a. Pro-Jection US$600 - 1,000 7. Racetech Engineering Bay G 1007 55th Ave.,NE Calgary, Canada T2E 6W1 a. SDS (Simple Digital Systems) EM-1 8. Advanced Automotive Electronics Ltd. Van Nuys House Scotlands Dr. Farnham Common Slough SL2-3ES England Phone: 01753-642019 Contact Brian Warburton email: bwarb@xxx.net a. Ignition Management System UK#395 b. Clubmans EFI system UK#495 c. Engine Management System (Ign & EFI) UK#755 d. Programming software - free with purchase 9. Plus 1 Micro, Inc. PO Box 1781 Lawrenceville, GA 30246-1781 a. InterACQ 10. Advanced Engine Management (Australia) 22 Melrich Rd. Bayswater, Victoria Australia Phone: (+613) 9761 3161 fax: (+613) 9761 3162 email steve@xxx.au Prices include basic wiring loom & sensors with no PC required. Supports rotary, 4, 6, & 8 cylinder engines. a. Wolf2D EFI with built in user I/O US$660 b. Wold3D EFI+IGN with detachable user I/O US$1030 Orin Harding - Greensboro, NC ('74 MGB-GT - '79 MGB Roadster with Electromotive TEC II) ------------------------------ From: orin@xxx. Harding) Date: Mon, 05 Feb 1996 11:24:01 -0500 Subject: DIY_EFI Vendor List - Revised Revised #1 and added comparision list After Market DIY_EFI Systems: (BASE system prices shown. Usually doesn't include sensors) 1. Electromotive, Inc. 14004-J Willard Road Chantilly, VA. 22021 (703) 378-2444 All prices ECU only a. HPV-1 Direct fire, Distributorless Ignition US$439 (4 Cyl) UD$459 (6 Cyl) US$499 (8 Cyl) b. HPV-3B " " " " US$664 (4 Cyl) US$689 (6 Cyl) US$724 (8 Cyl) c. TEC-I Engine Management (Fuel&Ign Mgt.) US$1,500 (6 Cyl) US$1,550 (12 Cyl) d. TEC-II " " " " " US$999 (4 Cyl) US$1,029 (6 Cyl) US$1,069 (8 Cyl) e. Software for the above US$150 - 550 2. Haltech (Australia) US Distributor Performance Automotive Electronics 2158 W. Northwest Highway, Suite 400 Dallas, TX 75220 (214) 831-9800 All prices ECU only a. IG4 Ignition Control US$480 b. F7B EFI system US$640 c. F7C EFI system US$680 d. F9 EFI system US$680 e. E6 EFI system US$960 2a. EFI (Haltech) Unit 7 130 Taren Point Road Taren Point 2229 Sydney Australia 3. Mr. Gasket 8700 Brookpark Rd. Cleveland, OH 44129 (216) 398-8300 Contact Mark Hamel (X488) 3a. ACCEL - Same address and phone 3b. Digital Fuel Injection (DFI)- Owned by Mr. Gasket 37732 Hills Tech Dr. Farmington Hills, MI 48024 a. 74040A Universal US$740 b. 74022L (Chev 350) US$900 c. Calmap software US$185 4. Emtech (Australia) 5. NOS/EFI Tech. 6. Holley 11955 E. Nine Mile Road Warren, MI 48089-2003 a. Pro-Jection US$600 - 1,000 7. Racetech Engineering Bay G 1007 55th Ave.,NE Calgary, Canada T2E 6W1 a. SDS (Simple Digital Systems) EM-1 8. Advanced Automotive Electronics Ltd. Van Nuys House Scotlands Dr. Farnham Common Slough SL2-3ES England Phone: 01753-642019 Contact Brian Warburton email: bwarb@xxx.net a. Ignition Management System UK#395 b. Clubmans EFI system UK#495 c. Engine Management System (Ign & EFI) UK#755 d. Programming software - free with purchase 9. Plus 1 Micro, Inc. PO Box 1781 Lawrenceville, GA 30246-1781 a. InterACQ 10. Advanced Engine Management (Australia) 22 Melrich Rd. Bayswater, Victoria Australia Phone: (+613) 9761 3161 fax: (+613) 9761 3162 email steve@xxx.au Prices include basic wiring loom & sensors with no PC required. Supports rotary, 4, 6, & 8 cylinder engines. a. Wolf2D EFI with built in user I/O US$660 b. Wold3D EFI+IGN with detachable user I/O US$1030 Manufacturer #1 #2 #3 Model TEC II E6 74040A PC I/O yes yes yes Prog. offline yes yes no Inj. drivers 2 8 4 Additional drivers yes($) Seq. Inj. yes($) no yes($) Fuel Map yes yes yes # fuel maps by RPM 8 16 Prog. points/RPM 8 8 Total prog. points 64 256 Warm-up Map yes yes yes Idle control yes(GM ICM) no yes(GM ICM) Data logging yes($) yes yes Speed density yes yes yes Mass Air Flow yes($) no no EGO - Closed loop yes yes yes Gen. purpose output yes yes Ignition control yes yes yes Ign. amp. needed no yes yes Ign. map points 64 yes Detonation sensor yes no yes Manufacturer #6 #7 Model Projection SDS PC I/O no no Prog. offline no Inj. drivers Additional drivers Seq. Inj. Fuel Map # fuel maps by RPM Prog. points/RPM Total prog. points Warm-up Map Idle control Data logging Speed density Mass Air Flow EGO - Closed loop Gen. purpose output Ignition control Ign. amp. needed Ign. map points Detonation sensor Manufacturer #8 #8 #8 Model Ign. Mgt. Clubmans Eng. Mgt. Sys. PC I/O yes yes yes Prog. offline Inj. drivers n/a 1 4 Additional drivers n/a yes (+#) yes (+#) Seq. Inj. n/a no yes Fuel Map n/a yes yes # fuel maps by RPM n/a 16 16 Prog. points/RPM n/a 24 24 Total prog. points n/a 384 384 Warm-up Map n/a Idle control n/a yes (?) Data logging yes yes yes Speed density n/a yes yes Mass Air Flow n/a EGO - Closed loop n/a no yes Gen. purpose output Ignition control yes yes yes Ign. amp. needed no no no Ign. map points 384 384 384 Detonation sensor no no yes Manufacturer #10 #10 Model Wolf2D Wold3D PC I/O no no Prog. offline Inj. drivers Additional drivers Seq. Inj. Fuel Map # fuel maps by RPM Prog. points/RPM Total prog. points Warm-up Map Idle control Data logging Speed density Mass Air Flow EGO - Closed loop Gen. purpose output Ignition control no yes Ign. amp. needed Ign. map points Detonation sensor Orin Harding - Greensboro, NC ('74 MGB-GT - '79 MGB Roadster with Electromotive TEC II) ------------------------------ From: orin@xxx. Harding) Date: Mon, 05 Feb 1996 11:23:55 -0500 Subject: DIY_EFI Vendor List - Revised Revised #1 and added comparision list After Market DIY_EFI Systems: (BASE system prices shown. Usually doesn't include sensors) 1. Electromotive, Inc. 14004-J Willard Road Chantilly, VA. 22021 (703) 378-2444 All prices ECU only a. HPV-1 Direct fire, Distributorless Ignition US$439 (4 Cyl) UD$459 (6 Cyl) US$499 (8 Cyl) b. HPV-3B " " " " US$664 (4 Cyl) US$689 (6 Cyl) US$724 (8 Cyl) c. TEC-I Engine Management (Fuel&Ign Mgt.) US$1,500 (6 Cyl) US$1,550 (12 Cyl) d. TEC-II " " " " " US$999 (4 Cyl) US$1,029 (6 Cyl) US$1,069 (8 Cyl) e. Software for the above US$150 - 550 2. Haltech (Australia) US Distributor Performance Automotive Electronics 2158 W. Northwest Highway, Suite 400 Dallas, TX 75220 (214) 831-9800 All prices ECU only a. IG4 Ignition Control US$480 b. F7B EFI system US$640 c. F7C EFI system US$680 d. F9 EFI system US$680 e. E6 EFI system US$960 2a. EFI (Haltech) Unit 7 130 Taren Point Road Taren Point 2229 Sydney Australia 3. Mr. Gasket 8700 Brookpark Rd. Cleveland, OH 44129 (216) 398-8300 Contact Mark Hamel (X488) 3a. ACCEL - Same address and phone 3b. Digital Fuel Injection (DFI)- Owned by Mr. Gasket 37732 Hills Tech Dr. Farmington Hills, MI 48024 a. 74040A Universal US$740 b. 74022L (Chev 350) US$900 c. Calmap software US$185 4. Emtech (Australia) 5. NOS/EFI Tech. 6. Holley 11955 E. Nine Mile Road Warren, MI 48089-2003 a. Pro-Jection US$600 - 1,000 7. Racetech Engineering Bay G 1007 55th Ave.,NE Calgary, Canada T2E 6W1 a. SDS (Simple Digital Systems) EM-1 8. Advanced Automotive Electronics Ltd. Van Nuys House Scotlands Dr. Farnham Common Slough SL2-3ES England Phone: 01753-642019 Contact Brian Warburton email: bwarb@xxx.net a. Ignition Management System UK#395 b. Clubmans EFI system UK#495 c. Engine Management System (Ign & EFI) UK#755 d. Programming software - free with purchase 9. Plus 1 Micro, Inc. PO Box 1781 Lawrenceville, GA 30246-1781 a. InterACQ 10. Advanced Engine Management (Australia) 22 Melrich Rd. Bayswater, Victoria Australia Phone: (+613) 9761 3161 fax: (+613) 9761 3162 email steve@xxx.au Prices include basic wiring loom & sensors with no PC required. Supports rotary, 4, 6, & 8 cylinder engines. a. Wolf2D EFI with built in user I/O US$660 b. Wold3D EFI+IGN with detachable user I/O US$1030 Manufacturer #1 #2 #3 Model TEC II E6 74040A PC I/O yes yes yes Prog. offline yes yes no Inj. drivers 2 8 4 Additional drivers yes($) Seq. Inj. yes($) no yes($) Fuel Map yes yes yes # fuel maps by RPM 8 16 Prog. points/RPM 8 8 Total prog. points 64 256 Warm-up Map yes yes yes Idle control yes(GM ICM) no yes(GM ICM) Data logging yes($) yes yes Speed density yes yes yes Mass Air Flow yes($) no no EGO - Closed loop yes yes yes Gen. purpose output yes yes Ignition control yes yes yes Ign. amp. needed no yes yes Ign. map points 64 yes Detonation sensor yes no yes Manufacturer #6 #7 Model Projection SDS PC I/O no no Prog. offline no Inj. drivers Additional drivers Seq. Inj. Fuel Map # fuel maps by RPM Prog. points/RPM Total prog. points Warm-up Map Idle control Data logging Speed density Mass Air Flow EGO - Closed loop Gen. purpose output Ignition control Ign. amp. needed Ign. map points Detonation sensor Manufacturer #8 #8 #8 Model Ign. Mgt. Clubmans Eng. Mgt. Sys. PC I/O yes yes yes Prog. offline Inj. drivers n/a 1 4 Additional drivers n/a yes (+#) yes (+#) Seq. Inj. n/a no yes Fuel Map n/a yes yes # fuel maps by RPM n/a 16 16 Prog. points/RPM n/a 24 24 Total prog. points n/a 384 384 Warm-up Map n/a Idle control n/a yes (?) Data logging yes yes yes Speed density n/a yes yes Mass Air Flow n/a EGO - Closed loop n/a no yes Gen. purpose output Ignition control yes yes yes Ign. amp. needed no no no Ign. map points 384 384 384 Detonation sensor no no yes Manufacturer #10 #10 Model Wolf2D Wold3D PC I/O no no Prog. offline Inj. drivers Additional drivers Seq. Inj. Fuel Map # fuel maps by RPM Prog. points/RPM Total prog. points Warm-up Map Idle control Data logging Speed density Mass Air Flow EGO - Closed loop Gen. purpose output Ignition control no yes Ign. amp. needed Ign. map points Detonation sensor Orin Harding - Greensboro, NC ('74 MGB-GT - '79 MGB Roadster with Electromotive TEC II) ------------------------------ From: "Zublin, Bryan (SD-MS)" Date: Mon, 05 Feb 1996 09:48:00 -0800 (PST) Subject: RE: Ford MAF sensor >It is my understanding that the Ford E8ZZ-12B579-A sensor is rated at 891 >kg/hr air flow or approx. 230 HP max...Does Ford have a similar sensor in the >110 - 130 hp range?? Try the 4 cylinder Ford engines, maybe the 1.9L (?) engine in the Mercury Tracer (same as Ford Escort?). Or if you want a little more flow capability, try the (standard horsepower) 6 cylinder engines. The Taurus SHO makes over 200 hp, so it's MAF is similar in size to the 5 liter V8. The last few years that I went to the San Diego auto show, it seemed that all of the Ford engines had the same style of MAF, with the only difference being the diameter (ie. flow capability). Bryan Zublin bzublin@xxx.com ------------------------------ From: pjwales@xxx.net (Peter Wales) Date: Mon, 05 Feb 1996 13:00:29 -0500 Subject: Re: Spellcheckers >Peter, with all due respect, one of the biggest problems the U.S. has >is that it is blisfully ignorant of other cultures. English is not >the only language spoken in the world. In fact, I believe it is >*third*. A quick look at this guy's name and location will tell you >that this guy's mother tongue is French. If you spoke French you >would understand why he spells like that in English. I did look at and note his address, and said "up there". I prefer to disagree with you on the spelling being in french. It just looks bad to me. >I thinks he did >quite well....you understood what he was trying to say -right ? No, and that was the reason for the comment. Working my way through all of the spelling errors became such hard work that I gave up and went onto the next posting. Therefore, if I had been able to contribute anything to the reply, I wouldn't have, because it would have been too much like hard work. This is why there are spell checkers, so that simple errors can be eliminated by the computer. Poor English is a different story, and my French would be a lot worse than his English, but I would try and run it through a spell checker to get some sort of chance of the best possible responses to my questions. If the guy didn't speak English then the grammar and text content would be very different and then everything would be excusable. > How about some slack ? > Ok,you answer the question, I'm off to the next posting >Mark Hillier >mhillier@xxx.com >Montreal, Canada Peter Wales President Superchips Inc Florida Chairman Superchips Ltd Buckingham "Timing is everything" Superchips home page with all the answers http://www.superchips.com ------------------------------ From: m_mcdonald@xxx.com Date: Mon, 5 Feb 96 13:10:01 EST Subject: Engine codes; PC to General Motors ALDL interface > George M. Dailey (gmd@xxx.com) said: > Does Diacom have and any idea about their massive following? I hope that Rinda Technologies (maker of the DIACOM hardware/software package) has a massive following. DIACOM IMHO is an excellent product and very fairly priced at about $300. > The latest > J.C. Witney catalog #586k (inside cover page) has an Auto Xray XP240 scanner > for $280 complete, no PC needed. The illustration shows a two line display > (32 characters). Interface cables are available for GM (king of autos), Ford > :-}, and that other car maker ... Chrysler for only $29 each. I do not own > one, and I don't know anybody that owns one. I'd be willing to bet that it > works as advertised. My only experience with the Auto Xray scanner is reading its advertisement. It may be OK for GM and Chrysler owners since it displays information from their cars' serial data stream. It only displays trouble codes for Ford products. This makes it by far the most expensive Ford code reader in existence. > I neglected to tell you folks out in DIY FI land, what my true reason was > for wanting to read ALDL data. > Here's my confession. I have constructed a mid engine, rear wheel driven > sports car from scratch. The engine is a '85 PFI 3.8L Buick V6. The plan is > to transmit the ALDl data to a dedicated PC, peramanently mounted in the car > and connected to a small VGA monitor. Software would convert the data to > usefull information that would be displayed on the monitor. Boom, no > additional instruments needed and a wealth of data on demand. The car > (Bianca) was designed to house a PC. Think of her as a streached > Lamborghini Contach with all the room and comfort of a full size '70's Olds. > Data logging would also be utilized. The PC would also control some BODY > functions. It's not that I'm to cheap to by Diacom or XP240 (I just might by > the XP240) but, if I'm going to make this work I need to get some type of > simple PC to ALDL communication established. > Any help on the software end would be much needed. I'll begin by congratulating George on his construction and enthusiasm. As soon as you decide to *control* body (or any component) function from a PC, you are in another ball game. I believe that DIACOM uses some fairly sophisticated programming to extract information from the data streams (I think there are four streams, not just one) at the ALDL. Learning the many details of these data streams is a difficult task. Learning how to write a program to perform I/O at a PC's parallel port requires a large amount of time for a beginner. Perhaps you can take advantage of what DIY_EFI members have done to control the engine functions and modify this software? Other members may have advice and suggestions, more promising than mine are, to George. If so, speak up! > thanks' > George M. Dailey gmd@xxx.com Marll McDonald KB1AGM m_mcdonald@xxx.com ------------------------------ From: "Zublin, Bryan (SD-MS)" Date: Mon, 05 Feb 1996 10:42:00 -0800 (PST) Subject: RE: re: Re: Sensor Questions? Clint writes: >Quick question: what exactly is going to cause this "sudden increase in the >amount of required air" that is going to draw a vacuum? I don't know all of the physics behind it, but it is related to the velocity and inertia of the air, length of intake track, etc. The previous post about "acceleration enrichment strategies that are a function of throttle transients" was correct and is how the computer compensates for this condition. >Just remember that a MAF system also has to be calibrated to the engine it is >on. The MAF give out a voltage (or frequency) depending on how much air is >going through it. It does not tell you "currently, there is x Kg/sec flowing >through me". Excuse me? That's exactly what the MAF *does* tell you: mass air flow (kg/hr) flowing through the meter and into the engine. That's the beauty of the MAF. Pressure, temperature, and density variations do not have a (large) effect on the accuracy. Bryan Zublin bzublin@xxx.com ------------------------------ From: dn Date: Mon, 5 Feb 96 11:47:09 MDT Subject: Re: IAC Dan wrote: > On the subject of the GM IAC(idle air controller) for the TPI engines. > Does anyone know of a replacement, working of sensing the temperature > or similar, ie. some sort of bi-metal spring system. The problem is The IAC is a stepper motor controlled by the ECU. The ECU stores a reference position when the engine is shut off, and closes the valve so it knows where it is on start up (open loop, no position feedback from the IAC). The IAC is controlled by engine RPM, it adjusts idle speed according to engine load. Think of it as a small throttle plate bypassing the main throttle body. Only way I can think of to make it work without ECU control is to design a small processor board to emulate the ECU signals. This would require an input from the ignition system (to determine RPM) and stepper motor driver software with a driver chip or discrete transistor output. Simply write the code to adjust the IAC in or out (in real time) until the idle speed is what you want, after that anything that affects idle (temperature, A/C, alternator load, auto transmission in gear, etc.) would be compensated for by the processor. (this would be a good application for a BASIC stamp). I don't know for sure if you could just bypass it, I think it is necessary to have it hooked up in order for the engine to get enough air at idle. Can't remember if there is a separate idle speed screw on the throttle body. You could maybe adjust the thing by removing it and rotating the pintle until you get the idle speed you want, and just leave it there, but you won't have any warmup fast idle or other compensation. You might also be able to hack off the motor end of the thing, so you can rotate the shaft and have a manual adjustment |-( regards, dn - -- - --------------------------------------------------------------------- Darrell A. Norquay Internet: dn@xxx.ca Datalog Technology Inc. Bang: calgary!debug!dlogtech!darrell Calgary, Alberta, Canada Voice: +1 (403) 243-2220 Fax: +1 (403) 243-2872 @ + < __/ "Absolutum Obsoletum" - If it works, it's obsolete -------------------------------------------------------------------- ------------------------------ From: Date: Mon, 5 Feb 96 09:51:05 -0600 (CST) Subject: fwd: What about H202 Comments By: Steve Ravet@Prj Eng@PCPD Hou Originally To: Originally From: Hotrod List Original Date: 2/2/96 12:09 PM Comments: I thought this was a very interesting question from the hotrod list. Any comments? I'll forward them back to the hotrod list... - --steve Steve Ravet sravet@xxx.com Baby you're a genius when it comes to cooking up some chili sauce... - -------------------------[Original Message]-------------------------- I've been thinking on and off for a while about hydrogen peroxide injection. It would seem to have all of the benefits of water injection, plus some of the benifits of nitrous oxide injection. The question in my mind is "why is this not done?". The only answer I can come up with is that H2O2 looses its O too early in the combustion process ( with respect to N20 ) and thus has an effect similar to straight O2 -- explosion in the wrong place at the wrong time. Does anybody have any experience in, or references to, the subject? Thanks in advance. Frank Evan Perdicaro Dainippon Screen Engineering of America Legalize guns, drugs and cash...today. 3700 Segerstrom Ave inhouse: frank@server, x258 Santa Ana CA outhouse: frank@xxx.com, 714-546-9491x258 92704 DoD:1097 ------------------------------ From: James Patterson Date: Mon, 5 Feb 1996 12:52:00 EST Subject: Re: IAC ** Reply to note from dn 02/05/96 11:47am MDT > Dan wrote: > The IAC is a stepper motor controlled by the ECU. The ECU stores a reference > position when the engine is shut off, and closes the valve so it knows where > it is on start up (open loop, no position feedback from the IAC). > > I don't know for sure if you could just bypass it, I think it is necessary > to have it hooked up in order for the engine to get enough air at idle. Can't > remember if there is a separate idle speed screw on the throttle body. You > could maybe adjust the thing by removing it and rotating the pintle until > you get the idle speed you want, and just leave it there, but you won't have > any warmup fast idle or other compensation. You might also be able to hack > off the motor end of the thing, so you can rotate the shaft and have a manual > adjustment It would be simple enough to put a 3 position switch (on-off-on) wired into the IAC to manualy control speed. The voltage ( I believe 5v) would have to be supplied. The switch could be mounted in the cabin and allow the driver to adjust for various conditions. The IAC holds its last position so you should not have to adjust at every startup. James Patterson james@xxx.edu ------------------------------ From: Bill Date: Mon, 05 Feb 1996 20:35:43 -0800 Subject: RE: re: Re: Sensor Questions? At 10:42 AM 2/5/96 -0800, you wrote: > >Clint writes: > >>Quick question: what exactly is going to cause this "sudden increase in the >>amount of required air" that is going to draw a vacuum? > >I don't know all of the physics behind it, but it is related to the velocity >and inertia of the air, length of intake track, etc. The previous post >about "acceleration enrichment strategies that are a function of throttle >transients" was correct and is how the computer compensates for this >condition. > >>Just remember that a MAF system also has to be calibrated to the engine it >is >>on. The MAF give out a voltage (or frequency) depending on how much air is >>going through it. It does not tell you "currently, there is x Kg/sec >flowing >>through me". > >Excuse me? That's exactly what the MAF *does* tell you: mass air flow >(kg/hr) flowing through the meter and into the engine. That's the beauty of >the MAF. Pressure, temperature, and density variations do not have a >(large) effect on the accuracy. > >Bryan Zublin >bzublin@xxx.com > > I think what Clint is saying is that the MAF produces a frequency or voltage PROPORTIONAL to the mass of air currently passing through it, rather than a binary or BCD number showing exactly what the current flow is.....its all a matter of the way he phrased the statement. With any 2-wire device, it's usually the user's responsibility to decode the data into some meaningful result. ------------------------------ From: gavin@xxx.au (Gavin Walker) Date: Tue, 6 Feb 1996 13:21:40 +1100 (EST) Subject: Electronic thottles Hi Guys I read recently that as part of the Merc skid control system they switched to using a remote throttle. i.e. there is no cable connecting the pedal and the throttle. Are the current stepping motors sufficiently quick for this? I can see advantages in idle control, gear selection and dual throttle bodies. Well the volume of this list is getting too much for the moment so I've sign off for the next few months. When I get closer to materialising my project I'll hop back on. See you guys later. 1978 Toyota Corolla KE50 Liftback 1.2l 3K-C 8ohv 275 000km 1992 Mitsubishi Lancer CC GLXi Hatch 1.6l SOHC16v 4G92 60 000km 1967 Rover P6 2000 SC Sedan SOHC8v ?15 000miles - -- _--_|\ -|- Gavin Walker / \ | \_.--.*/ <- Canberra, gavin.walker@xxx.au v Australia Phone +61-6-2167030 Fax +61-6-2167111 ------------------------------ End of DIY_EFI Digest V1 #33 **************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".