DIY_EFI Digest Friday, 25 October 1996 Volume 01 : Number 324 In this issue: Re[2]: We're clever people Idle control valve Bosch O2 Sensor Question Re: Idle control valve Wide range O2 sensors Re[3]: We're clever people Re: Idle control valve See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Mcgonegal.Will@xxx.ca Date: Thu, 24 Oct 96 08:01:05 EST Subject: Re[2]: We're clever people >>>inspectors. (And perhaps it will be illegal, I don't care) >> Not a very "clever" thing to say on an open line in this day-and-age. Daniel Ridge from Research Minion, Beowulf Project wrote >I can personally assure you that I can write whatever I wish here and the >people who check my emissions still won't know me from a hole in the >wall. >I seriously doubt that the powers that be have the free time to be >reading, the drive space to be storing, or the spare cycles to be later >sifting through my email. Oh, really. Interesting. You never know who else may be reading AND actually taking notes. Will McGonegal Mobile Sources Emissions Division (Vehicle Emissions Testing Laboratory) Environment Canada (Canada's "EPA") ------------------------------ From: jwest@xxx.edu (Joe West) Date: Thu, 24 Oct 1996 10:38:18 -0600 Subject: Idle control valve Greetings All. I have a question concerning the idle system used in EFI. How fast and what factors are involved in the closing of the idle control valve once the throttle plates have opened ? Thanks in advance Joe Joseph D. West Electronics Lab. Supervisor College of Mechanical Eng. Ohio State University (614) 292-2845 Fax (614) 292-3163 ------------------------------ From: Brad Anesi Date: Thu, 24 Oct 1996 08:01:16 -0600 Subject: Bosch O2 Sensor Question Here's another O2 sensor question... Does the "universal" Bosch 3-wire sensor (part # 0 258 003 000) have the same spec's as the one with the connector built in for my Alfa? (0 258 003 101 - current Bosch reco' or 0 258 003 061 - original) Thanks, Brad '86 911 Coupe '91 Alfa 164 P.S. Bosch technical support was of no value other than to look up the current p/n. ------------------------------ From: Paul Beam Date: Thu, 24 Oct 1996 13:59:37 -0400 Subject: Re: Idle control valve >I have a question concerning the idle system used in EFI. How fast and what >factors are involved in the closing of the idle control valve once the >throttle plates have opened ? I worked a little on this at Saturn, before they were actually selling cars. GM uses a stepper motor like valve, while some others, including Ford, use a solenoid type system they control with PWM. If I understand your question, I left the valve alone once the engine was no longer under idle conditions. I seem to recall that you want to control the speed of the engine while the vehicle is below a certain speed, but the car is moving you just leave it alone. The powertrain people there told me that was how it was done. My system would actually help someone start in a manual transmission car by allowing more air (and hence fuel) into the engine as they would start to move. Under deceleration, you can let the engine "race" until the vehicle gets down to 15 mph or so. You should be able to simulate this on a manual transmission car by pushing in the clutch while rolling down the highway and see what happens. The only other issues are how fast can you make changes and how big. The answers are not often and not very much. A couple of times a second is the most you can get away with. If you add too much air, you will kill the thing unless you "cheat" and richen the mixture with an extra shot of combustibles. Again, this is how I did it on a hybrid GM system. I'm not sure what others have done. Paul R Paul Beam Computer Systems Engineer Johnson Bible College 7900 Johnson Drive Knoxville, TN 37998 (423) 573-4517 (423) 579-2337 fax ------------------------------ From: Chris Wilson Date: Thu, 24 Oct 1996 23:08:08 +0100 Subject: Wide range O2 sensors Any pricing info on wide range O2 sensors in the USA? Here in the UK they are ridiculously expensive,probably because we are about 10 years behind the USA in emissions legislation and associated hardware. The kind of device I am looking for is one that will read well above the normal range,for engine dyno development work.Bosch does a Motorsports one,but too dear....;-) - -- Chris Wilson Thu, 24 Oct 1996 19:29 +0100 Gatesgarth Racing Developments Gatley,Cheshire,U.K. Race Car Preparation and Development http://195.102.33.46/~gategart mailto:chris@xxx.com ------------------------------ From: dzorde@xxx.au Date: Fri, 25 Oct 96 08:16:57 Subject: Re[3]: We're clever people Good to see that we have fellow diy'ers on the inside, guess you guys now know where to go every year to get a pass. Fortunately Western Australia don't have this ridiculous law (WELL NOT YET ANYWAY), so we're enjoying while we can. Dan dzorde@xxx.au ______________________________ Reply Separator _________________________________ Subject: Re[2]: We're clever people Author: diy_efi@xxx.edu at INTERNET Date: 10/24/96 10:13 PM Oh, really. Interesting. You never know who else may be reading AND actually taking notes. Will McGonegal Mobile Sources Emissions Division (Vehicle Emissions Testing Laboratory) Environment Canada (Canada's "EPA") ------------------------------ From: "George M. Dailey" Date: Thu, 24 Oct 1996 18:56:49 -0500 (CDT) Subject: Re: Idle control valve At 10:38 AM 10/24/96 -0600, you wrote: > > >Greetings All. > >I have a question concerning the idle system used in EFI. How fast and what >factors are involved in the closing of the idle control valve once the >throttle plates have opened ? > >Thanks in advance >Joe > > >Joseph D. West >Electronics Lab. Supervisor >College of Mechanical Eng. >Ohio State University > >(614) 292-2845 >Fax (614) 292-3163 > It has been my observation that the stepper motor used in GM systems goes full open to full closed in about 2-4 seconds. I think when the speed is above 25mph the ecm either closes or opens the IAC valve. Probably to keep the stepper motor and associated parts from locking in place. I know for a fact that at some point the ecm will comand the IAC to shut and ecm will count the steps from the reference to establish the correct idle position. I guess it's forgetful, (second thing to go with age). GMD GMD ------------------------------ End of DIY_EFI Digest V1 #324 ***************************** 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".