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I have an 82 which has sat for several years. Cleaned tank and installed fuel pump and have it running. Good spray at the injectors, but poor drivability. Check Engine Light 12,12,12-51.51.51. Removed ECU and and EPROM cleaned all contact points as well as battery connections and junction box in battery compartment. But when looking at previous posts, the EPROM appeared to be in backwards. But when reversed, no codes- solid check engine light. Placed back as found and still 12,12,12-51,51,51. Manual says bad EPROM. When installing the EPROM, are the small cut in the EPROM supposed to match the cut in the holder as in the pic? If so, mine was in backwards! Might the ECU be bad also? THANKS for any suggestions.
Did not drive the car with the EPROM in position (with the indentions matching). Car started and Check engine light was ON. The fuse in the battery compartment?
[QUOTE=itsforfun;1597958980]Did not drive the car with the EPROM in position (with the indentions matching). Car started and Check engine light was ON. The fuse in the battery compartment?[/QUOTE.
Fuse box under driver side near brake on firewall.Upper rightside labeled ECM
It appears the EPROM is defective. Tried in both directions and same results. Ordered a Hypertech chip. Hope ECM os OK!
There is no guarantees -- but putting the prom in backwards will usually not hurt the ECM -- it WILL kill the PROM. I am not sure of your theory that both the half moons should be together -- you really need to look in the service manual to assure that you put it in correct.
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Yes, your orientation would be correct with the indents for the PROM and the fact that you put it in backwards and it didn't work means that you burned it up for sure and it will burn it up for sure every time you do that. The ECM board usually is fine and with the new chip, ensure you install it correctly and don't get the chip with the 160* stat feature, leave it at 195* or you may run into issues with a stock 82 CFI motor.
Yes - you're screwed. On a cold winter day in the tight space and with poor lighting I did the same thing as you did and blew out both the chip by reversing it - and yes, it blew out the ECM as well. I had to replace both. I highly recommend that you replace the chip with a HyperTech Streetrunner (previous postings - fixes lugging shift points and slightly improved drivabilit)) and Zip sells a reman ECM. It is a bear to remove the ECM unless you have a mirror to see a couple of the bolts - then, I reinstalled it on the protective plate with commercial grade Velcro instead of the hidden bolts spas not to deal with that job ever again.
UPDATE:
Installed the Hypertech Street Runner PROM with the indentions matching. Car starts and Check Engine light stays ON, but no codes displayed. I asssuming ECM is defective. Any way to check it- Codes say 55 indicated bad ECM.
UPDATE:
Installed the Hypertech Street Runner PROM with the indentions matching. Car starts and Check Engine light stays ON, but no codes displayed. I asssuming ECM is defective. Any way to check it- Codes say 55 indicated bad ECM.
The Hypertech Streetrunner chip may be blown, as well. That was my expensive experience. The past is the past - move forward.
Let me know if you need an intervention.
I may be going through this for my 1981 Question...would a reman ECU from Ecklers be the same as a re-manufactured ECM from lets say AutoZone, Advance Auto or my other parts house that I believe all come from 'Cardone' rebuilders?
Ecklers... $130.00
Advance Auto... $85.00
I would have no problem buying from Advanced Auto and saving the money. They are all rebuilt by Cardone
What seems sneaky on Ecklers behalf, they are stating their ECM is "remanufactured by ACDelco"...that's what made me ask my question about Cardone.
Many years back A1-Cardone did quality rebuilds (for the most part) and you got a good rebuilt part, since they have been (I believe) in Mexico, not so much.
Direct from Ecklers page below EDIT...I spoke to a Ecklers rep and was told "these ECM are rebuilt by ACDelco"...I'm still thinking inn Mexico or China etc but maybe under ACDelco's name, and only have a 90 day warranty.
Remanufactured By ACDelco
Save Big Money Versus New
No Core Required
Reuse Existing Chip (not included)
Last edited by Hamerdown; Sep 17, 2018 at 01:20 PM.
Got the new ECM and now have discovered the problem I had orienting the EPROM. My ECM did NOT have a "carrier" for the EPROM. The EPROM was installed directly on the ECM so it could go either way.. All instructions for the new EPROM install references placing the EPROM in the plastic carrier- then it can only be installed one way because of the shape of the access hole in the frame. It appears that the tiny indentions on the EPROM should NOT match the tiny indentions on the ECM. Anybody have a pic of the plastic carrier to verify this?
Thanks
It's a universally accepted convention in electronics that the chip and socket notches match on DIP components, so it'd be really odd to have an application where they didn't.
The GM chip carriers I have seen for newer stuff have some kind of notch or variation that is on the same end as the notch in the chip.
If you want to measure, the pin on the bottom left should be 5V and the pin on the top right should be 0V. The voltage will be reversed if the socket notch was backwards. This reversing of the supply voltage to the chip is why it gets destroyed when it's reversed.
82 EC and EPROM problems
