DIY_EFI Digest Friday, 8 August 1997 Volume 02 : Number 263 In this issue: Re: Bad MAP? Re: Delco EPROMS...Re: DIY_EFI Digest V2 #261 Re: TPI Questions Re: TPI Questions schematics Re: Delco EPROMS...Re: DIY_EFI Digest V2 #261 See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Fred Miranda Date: Thu, 7 Aug 1997 22:23:15 -0500 (CDT) Subject: Re: Bad MAP? Look in your manual for the vac/voltage chart and test it. I think HK$ even has some info for the units used with their VPCs. I got rid of mine and no longer have the info. Fred At 10:48 PM 8/7/97 -0500, you wrote: >I was hoping with all of the talk concerning MAP sensors that someone could >help me with this question. How can you tell if you MAP sensor is going or >gone bad?? I have had a few friends just change them randomly and notice an >improvment! There has to be a good way to test these sensors.... > > Thanks >James > >------------------------------------- >James J. Heck >jheck@xxx.org >http://www.heckconsulting.com/jheck/ > > > ------------------------------ From: Terry Martin Date: Thu, 07 Aug 1997 20:44:40 -0700 Subject: Re: Delco EPROMS...Re: DIY_EFI Digest V2 #261 Curtis L. Martin wrote: > Just for grins and giggles, does anyone know for certain what style of > EPROM is used? > > The ones used in the V6's are pretty easy.. they are 27xx series EPROMS. > The ones used on the V8's have me stumped: I've unloaded 2732(A), 27C128, 27C256, and variations dependant on manufacturer/#. Some interchange, some don't. Base I/O varies, and if not set device dependent doesn't matter. Controller type, year, make & model dependant, as well as plant, shift, sequential line #, ie. running assembly line changes do. The only constant is change. If you unload a PROM, the easiest way to burn a blank one is do your modifications in programmer ram and upload without setting the device limits or offset. Various later V-8's use EEPROMs. ------------------------------ From: Jennifer Rose Date: Thu, 07 Aug 1997 21:07:56 -0700 Subject: Re: TPI Questions At 09:58 AM 8/7/97 -0500, you wrote: Hi Jeff Not really good at this ,but here goes. > > >Question - I am installing a TPI unit on an older 350. (OK, that's not a >question) > >1. There are two coolant fittings on the throttle body. Do I need to >connect them and if so where to? The fitting in front goes to the in take manifold. The one on the side goes to the rad, or in my case the heater. > >2. There is a big fitting (vacuum) on the left side of the manifold kinda >hidden between the runners > (I think it's the left side) that I'm assuming is for power brakes, >can someone confirm that. PVC valve > >3. Any concerns with eliminating the EGR valve. Noy sure but, without egr there could be more pinging (detination) > >4. I'm considering not connecting the MAF for initial start-up. Is this a >good idea or am I overly concerned.... The check engine light will come on and ecm will use backup figures for fuel calulations. Like to do test run complete. > >5. What do I do with the P/N, O/D Request and 1st Gear inputs to the ECM >with an older 4-speed manual. (ECM is for a manual transmission.) If prom is from a manual trans car p/n switch shouldn't nessecary > >Any other suggestions or tips would greatly be appreciated... If ya don't have shop manual for year of car the tpi is out of - please get one > >Jeff > > > Vance ------------------------------ From: Jennifer Rose Date: Thu, 07 Aug 1997 21:06:25 -0700 Subject: Re: TPI Questions At 10:32 PM 8/7/97 -0400, you wrote: >> Thanks for the help. >> >> This P/N thing is confusing. I have the JTR book (and a bunch others) >and >> most say not to ground this pin. >> If I remember correctly something to do with idle and deceleration. >Should >> I be concerned???? >> I think a lot of this is tied to an automatic transmission, not manual. >Is >> this true? > >I left mine open..sortta. I'm using Aluminum Corvette heads that do not >have the internal EGR passages in combination with a '86 VIN "F" TPI >manifold. > >The EGR valve is still present and connected, but doesn't actually do >anything since there isn't a supply of exhaust gas to the valve. > >Grounding the EGR feedback wire will set off the SES light (it simulates >the EGR being stuck in the open position) > >Leaving it disconnected will also occasionally set off the SES light (there >are a few cases where the ECM will command the EGR to actuate, then look to >see what happened.) Fortunately, temps down here are high enough that this >doesn't happen often. (been about 4 months since the last time the code >went off) It will also clear itself within a few minutes of driving. > >Someday I'll have an EGR flange welded to one of the exhaust headers to >supply external EGR.. but it's a low priority. > >Curt Martin (cmartin@xxx.com) >Ormond Beach, FL >http://www.america.com/~cmartin >'87 350 TPI Camaro.. (used to be a 2.8L V6 :) > >If ya have a 165 ecm - the prom can be modified to disable egr error msg Vance PS sorry to append this to a long message ------------------------------ From: collet Date: Fri, 08 Aug 1997 06:54:27 +0200 Subject: schematics hi, about L-Jectronics Bosch EFI does any body can tell me where I can found schematics of the electronic board,or if some one had tried to draw it himself(so hard!), or if a specific electronic repair WWW exist. thanks a lot. ------------------------------ From: Nick Dolling Date: Fri, 08 Aug 1997 15:09:25 +0930 Subject: Re: Delco EPROMS...Re: DIY_EFI Digest V2 #261 Curtis L. Martin wrote: > > > > > Reading the PROM is actually quite simple. Get a PROM > > > Reader/Programmer. Get a dual inline header strip. Bend the long > > > pins outward so that they can be plugged into the Programmer > socket. > > > Plug your Memcal onto the pins sticking up (the pinout for the > Prom > > > is the first (I think 28 pins) of the header. Cut off the rest of > > > them and you can read (and burn an erased memcal). The trick is > not > > > reading or burning the EPROM; but, in knowing where the various > maps > > > are on the PROM and what they are doing. > I'm a newbie here, but here's a few questions related to this. 1) Yes, it's easy to copy/erase/reprogram memcals this way, but as said above, the trick is to know where the tables are and what they do. Is this common knowledge around these circles, or is it a closely guarded secret amongst those who know or have found out themselves? > Just for grins and giggles, does anyone know for certain what style of > EPROM is used? > > The ones used in the V6's are pretty easy.. they are 27xx series > EPROMS. > The ones used on the V8's have me stumped: > > I've got a few of them (all for various VIN "F" Camaro's) and have > taken a > them apart for a peek inside. Here in Australia, the GM Holden cars have been using Delco ECMs for probably around 10 years (please correct me if I'm wrong). As far as I know, they all have 27xxx compatible EPROMs. Plenty of them aren't marked as such, but I have personally read/reprogrammed them with the programmer set as such. The difference between models is mainly in the chip size. I have seen them ranging from 128kbit to 1Mbit. Also there are differences in the hybrids which are part of the memcal (calprom). The older ones used IC's, the newer ones have hybrid circuits, and the newest one has nothing other than the EPROM. > I would like to be able to dump the map out of the ones I have and > compare > them to see what values have changed... I'd just like to know how to > configure the EPROM reader to the correct type of chip. I would like to know where the tables are, and what they do. If anyone has this knowledge and is willing to share it I'd be very grateful. Cheers, Nick - -- o----Nick Dolling-------------------------------------------o o----Apexus Engineering Pty Ltd-----------------------------o o----email:ndolling@xxx.au---------------------------o o----Ph : +618 8266 6222 Fax : +618 8266 6333---------------o ------------------------------ End of DIY_EFI Digest V2 #263 ***************************** 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".