WTB an ECM

[vilant]

Hi All,
Haven't been around for awhile, from 10/1/14 til the end of this July, every moment of my free time has been completing a major home improvement. Exterior is 100%, still finishing up the inside. Anyway, I had nagging issue with my ECM, kept getting a Code 31. Did everything I could do to repair it, the last thing to do was to send in my ECM for reconditioning. Just got the bad news a few days ago that my ECM is bad, has been reconditioned before, and more than likely will be unrepairable. I won't know for sure for a few more months as the place that does the rebuilds has a ton of backlogs, even then the outcome is bleak.
So, I have a 3900 lb paperweight in my garage. What really bums me out is I just bought a spare plenum and injector housing, had Pete port it to 36mm, and bought Marc's chip over the winter. Had big plans, but now it's dead in the water. :frown:
If any one has a spare ECM then can sell, please let me know, I'm desperate. My car is useless without one and will be, until I get a new one or an alternative is created.
Thanks, Joe

[GOLDCYLON]

Two sold in June on EBay. You need to grab em fast as they don't up for sale often.

[vilant]

I'm always leery of buying on eBay for several reasons. I tried one of those Cardone ECM's before from a chain store that are on there now for $200+. Can't remember exactly what happened but I know it didn't work. My ECM works with the exception of Code 31 popping on after a little bit and shutting down the secondaries. Very annoying, but the car runs fine, just 75hp less and probably not as gas efficient :(

[GOLDCYLON]

I'm always leery of buying on eBay for several reasons. I tried one of those Cardone ECM's before from a chain store that are on there now for $200+. Can't remember exactly what happened but I know it didn't work. My ECM works with the exception of Code 31 popping on after a little bit and shutting down the secondaries. Very annoying, but the car runs fine, just 75hp less and probably not as gas efficient :(

I understand your concerns. However this is the reality of owning a 25 year old car. Along with the DIS module these are the top two HTF parts for our car. We tend to have to be beggars when it comes to find these parts vs. choosers. This being the case we are better off finding one on a car part out that was known to be previously working as the NOS ones are long gone. Good luck in your search maybe a part out opportunity will come in the future if the seller is willing to part with it minus the engine. It is indeed frustrating. If we may ask where did you send your for rebuilding ? GC

Oh the other HTF parts? Oil pump, thermostat housing etc

[vilant]

Yea, I know, your right. I'll keep an eye out there, but unfortunately being in construction, I only have access to a computer when I'm home. Chances are it will disappear before I even see it. Going to check the salvage yards too. Hopefully, someone will let go of their spare, for the right price ;)
Sent it to Jerry.

[lfalzarano]

Sorry the links don't come through, but copy and paste into your browser. These were recently posted.

http://bgshooters.com/?wpsc-product=1990-91-corvette-zr-1-ecm

I bought mine from the above, but if not check these out...

http://www.ebay.com/itm/like/320555841926?ul_noapp=true&chn=ps&lpid=82 (Beware, the price is too low to be true)

http://www.egmcartech.com/store/Corvette-Zr-1-Ecm-Ecu-Computer-1990-1995-Lt5-01228331-16163993_221790937925.html

http://www.ebay.com/itm/Engine-Control-Module-ECU-ECM-PCM-Engine-Control-Module-Reman-/231562061479?fits=Model%3ACorvette

Call these guys to confirm if their ECM is LT5 compatible

http://www.zip-corvette.com/catalog/product/view/id/10147/s/90-91-remanufactured-ecm-pcm/category/7752/

They offer the LT5 Memcal

http://www.zip-corvette.com/84-96-c4/electrical-components/corvette-computer-modules-ecm/year/1990.html

Good luck.

[-=Jeff=-]

Sorry the links don't come through, but copy and paste into your browser. These were recently posted.

http://bgshooters.com/?wpsc-product=1990-91-corvette-zr-1-ecm

I bought mine from the above, but if not check these out...

http://www.ebay.com/itm/like/320555841926?ul_noapp=true&chn=ps&lpid=82 (Beware, the price is too low to be true)

http://www.egmcartech.com/store/Corvette-Zr-1-Ecm-Ecu-Computer-1990-1995-Lt5-01228331-16163993_221790937925.html

http://www.ebay.com/itm/Engine-Control-Module-ECU-ECM-PCM-Engine-Control-Module-Reman-/231562061479?fits=Model%3ACorvette

Call these guys to confirm if their ECM is LT5 compatible

http://www.zip-corvette.com/catalog/product/view/id/10147/s/90-91-remanufactured-ecm-pcm/category/7752/

They offer the LT5 Memcal

http://www.zip-corvette.com/84-96-c4/electrical-components/corvette-computer-modules-ecm/year/1990.html

Good luck.

Those eBay links are for the L98 ECM

[GOLDCYLON]

Those eBay links are for the L98 ECM


Yep

[vilant]

I actually bought another ZR-1, lol. High miles and in rough shape but the ECM is original and works perfect (for now). Was going to take some unobtainium parts for myself then part the rest out. But it's already sold to another member minus some parts I want. It was a one owner all original w/ 85,000 mi. It saved my car and is going to save someone else's as well.

[A26B]

Well plug that puppy in and lets see if it solves your problem!!

[spork2367]

White racing products offers a rebuild service for like 650.00 (with a 300.00 core charge).

[lfalzarano]

OK then, let me search again.

Using I believe the 1990-91 LT5 ECM is PN 1228331,

These guys repair them for $449.
http://www.autoecmcomputerexchange.com/collections/engine-control-module/products/1228331

White Racing has one for $699
http://www.ebay.com/itm/Corvette-ZR-1-ECM-ECU-Computer-1990-1995-LT5-01228331-16163993-/321875221596?hash=item4af1421c5c

This one is $895, but with a $300 core return.

https://www.autoecmstore.com/collections/engine-control-module/products/1228331

I also believe that the LT5 ECM PN 16196394 works for 1990-95 with the correct Prom for that year installed. According to Mark Hailbeck. "The details of the testing are described below.

GM used three ECM part numbers across the six model years.
01228331 1990 to 1991.
16163993 1992 to about 1993 1/2.
16196394 about 1993 1/2 to 1995.

AC/Delco supplied the 16163993 as a remanufactured unit for repairs from about 2004 until about 2009. They shipped 16163993 regardless of what model year was ordered.

I removed a factory installed 1990 01228331 from a 1990 car. Then installed a 1995 BMCB calibration chip and installed the ECM on a 1995 car. Everything worked normally. The engine went into closed loop fuel control, it went into learning mode, the EGR worked normally, the ASR worked, the momentary contact full power key worked, and the engine data scanner displayed engine rpm with a resolution of 1 rpm. The ALDL data stream ran at 6.6 frames per second, just like a 1995 ECM.

I removed a factory installed 1995 16196394 ECM from a 1995 car. Then installed a 1990 AYBK calibration chip and installed the ECM on a 1990 car. Everything worked normally. The engine went into closed loop fuel control, it went into learning mode, the full power key worked. The engine data scanner displayed engine rpm with a resolution of 25 rpm. This is normal for a 1990 car. The ALDL data stream ran at 6.6 frames per second, just like a 1990 ECM.

A 16163993 ECM was tested in a 1995 car and it worked normally as a 1995 ECM would."

Based on a search for PN 16196394

http://www.gmpartsgiant.com/parts/gm-ecm-rem-16196394.html $220

http://www.autoecmcomputerexchange.com/products/16196394 $320

White Racing has one for $$649
http://www.whiteracingproducts.com/index.php?main_page=product_info&products_id=1475

Always contact the vendor by phone and confirm their return policy. Beware of the low price bargains...

[vilant]

Well plug that puppy in and lets see if it solves your problem!!

Put it in the other day and she fired right up with no issues or SES lights. Haven't had a chance to road test yet. Its been raining the past few days and now a hurricane may hit. Still have to put my cal pack in too and make sure that's OK.

[vilant]

OK then, let me search again.

Using I believe the 1990-91 LT5 ECM is PN 1228331,

These guys repair them for $449.
http://www.autoecmcomputerexchange.com/collections/engine-control-module/products/1228331

White Racing has one for $699
http://www.ebay.com/itm/Corvette-ZR-1-ECM-ECU-Computer-1990-1995-LT5-01228331-16163993-/321875221596?hash=item4af1421c5c

This one is $895, but with a $300 core return.

https://www.autoecmstore.com/collections/engine-control-module/products/1228331

I also believe that the LT5 ECM PN 16196394 works for 1990-95 with the correct Prom for that year installed. According to Mark Hailbeck. "The details of the testing are described below.

GM used three ECM part numbers across the six model years.
01228331 1990 to 1991.
16163993 1992 to about 1993 1/2.
16196394 about 1993 1/2 to 1995.

AC/Delco supplied the 16163993 as a remanufactured unit for repairs from about 2004 until about 2009. They shipped 16163993 regardless of what model year was ordered.

I removed a factory installed 1990 01228331 from a 1990 car. Then installed a 1995 BMCB calibration chip and installed the ECM on a 1995 car. Everything worked normally. The engine went into closed loop fuel control, it went into learning mode, the EGR worked normally, the ASR worked, the momentary contact full power key worked, and the engine data scanner displayed engine rpm with a resolution of 1 rpm. The ALDL data stream ran at 6.6 frames per second, just like a 1995 ECM.

I removed a factory installed 1995 16196394 ECM from a 1995 car. Then installed a 1990 AYBK calibration chip and installed the ECM on a 1990 car. Everything worked normally. The engine went into closed loop fuel control, it went into learning mode, the full power key worked. The engine data scanner displayed engine rpm with a resolution of 25 rpm. This is normal for a 1990 car. The ALDL data stream ran at 6.6 frames per second, just like a 1990 ECM.

A 16163993 ECM was tested in a 1995 car and it worked normally as a 1995 ECM would."

Based on a search for PN 16196394

http://www.gmpartsgiant.com/parts/gm-ecm-rem-16196394.html $220

http://www.autoecmcomputerexchange.com/products/16196394 $320

White Racing has one for $$649
http://www.whiteracingproducts.com/index.php?main_page=product_info&products_id=1475

Always contact the vendor by phone and confirm their return policy. Beware of the low price bargains...
The one from White just popped on eBay. I've been watching eBay for a while and most of the ones on there will not work in my car. I bought one of those Cardone remans before from a chain store and it did not work. Maybe its my cal pack, I'll be testing that soon to make sure, but I don't think so. If you're going to use a rebuild service just use Jerry, I did. He offers it too, reasonable price and trustworthy. The reason I was looking for another ECM was my car was dead until the rebuild is done, and possibly may be unrepairable. Either way I need a back up and luckily found one.

[lfalzarano]

Conform the return policy before you buy, especially if you are not going to slap it in and test it right away.

Good Luck

[XfireZ51]

Any of the three ECMs will work for any year ZR with a prom burned w correct broadcast code for respective model year.
Any prom can be burned w any broadcast code. However, the prom must have the correct knock sensor (LT-5) on-board circuit. 1990 LT-5s had external(not on memcal) knock sensor circuit.

[RussMcB]

DIYAutoTune.com (MegaSquirt) is now offering an LT5 Engine Management Computer.

[vilant]

I have an ACDelco reman LT5 ECM, PN 16196394, still in the sealed GM box.

$700.00

no core charge

email if interested: finspeed@netmotive.net
Actually bought a whole car just for the ECM and other parts, then turned around and sold it for a parts car. Of course that ECM is a little flaky too, but better than my original. If my original ECM is unrepairable I will buy it from you if it's still available.

[Hib Halverson]

Actually bought a whole car just for the ECM and other parts, then turned around and sold it for a parts car. Of course that ECM is a little flaky too, but better than my original. If my original ECM is unrepairable I will buy it from you if it's still available.

I'm sorry, but I changed my mind about selling it.

I'm going to wait until I get my '95 sold and then I'll put the ECM and all the other parts I have up for sale.

[batchman]

DIYAutoTune.com (MegaSquirt) is now offering an LT5 Engine Management Computer.

In event of failure this has been my plan for a while, glad to hear they've got something cooked up.

Recently learned that one somewhat common failure modes on other GM ECMs of this era revolves a reference voltage (supply to the sensors) going out of whack, to the point of killing things like TPS's. Occurred to me it may be sensible to try to monitor and record the voltage in place so if this failure mode kicks in (like at Nats, 1600mi from home) there is at least a chance to cut a wire and add a precision voltage supply... It'd be a hack fix but could beat trying to scare up a co-drive...

Cheers,
- Jeff

[-=Jeff=-]

DIYAutoTune.com (MegaSquirt) is now offering an LT5 Engine Management Computer.

I don't see it on their website
Is it still around $3k?

[Scrrem]

DIYAutoTune.com (MegaSquirt) is now offering an LT5 Engine Management Computer.

MegaSquirt fitted a car here in WAZOO land with an early test unit and it had issues interfacing with the security system and a few other bugs I can't remember at the moment. Hopefully they ironed everything out on their final product.
Rich

[RussMcB]

I'm driving around with their unit now (for about a week). My engine is running great. I do think I've lost some dash functionality. I've noticed I'm not seeing my average MPG, maybe some other things. It's still early in my experience with it, so I'm sure there's more I'll learn about it. I lent my car to them for a few weeks so they had a test mule. I think they said there were a few things they have not yet been able to reverse-engineer. They thought they had come across some original GM/Lotus engineering documents but it turned out to be non-LT5.

Interestingly, even though I was plenty happy with my wired-open secondaries and MH chip, they convinced me to reinstall my secondaries system, because they said the car makes better low-end power with the secondaries operational, and they are able to better control the secondaries than the 1990's software. I'm trying to get back to the same chassis dyno I went to last time to compare to my last runs to know for sure if there is an improvement.

[-=Jeff=-]

I am surprised those functions on the LCD are not working, I would have thought for the $$ on the ECM it was going to work with everything.. Still would like to know what the cost is for one..

[RussMcB]

Sorry. I don't know the pricing. You could ask them here: https://www.diyautotune.com/catalog/contact_us.php

When I asked about the dash display functions they responded, "Some minor functions like trip computer will no longer work due to not having GM's serial protocols fully reverse engineered". He also said those don't affect the engine functions.

I agree it's not great to lose some original functionality. People will need to weigh the pros and cons to decide if it's worth it for them. It is pretty great to now have an option for when you just can't get a working GM ECU any longer, and it does offer way more options for custom tuning. Maybe by that time the dash functions will work (but I wouldn't hold my breath. That's probably not the best area for them to spend their time considering the market size).