HELP!!!!!

I'm pulling code 52 out of the ecm.
I've replaced the ecm and prom chip and it's still driving terrible.

What do I do?????

Greetings DOzER,

If You are still getting a code 52 after replacing the ECM and chip, you might start checking to make sure that all the wires are firmly seated in the ECM connector and that none of them are damaged or bare.
graemlins/beers.gif

The Trickster!!!!!!!!!!!!!!

Okay...I'll try that.

I've also read something about a Calpack...is that the same as the prom?

p.s.

The mechanic I originally took it to had no clue what the problem was!

Greetings DOzER,

Yes, the calpac is the same as the prom chip, they changed the name on it to make it sound more technical and confuse us poor shade tree mechanics. As for the mechanic you took it to not having a clue, unfortunately I have found this to be quite common a lot of times. This is not to say there aren't a lot of good mechanics out there. I have just found that a lot of places want good mechanics but are unwilling to pay them what they are worth.
graemlins/beers.gif

The Trickster!!!!!!!!!!!!!!!!

I guess I wouldn't call him a bad mechanic. He did a lot of free work to try and find out what the problem was. After cutting the catalytic converter off and welding it back in place...he pretty much threw up his hands and said it was the computer. I'll take your advice and check the wires...if it's not that...than I don't know what to do!

How about a ground problem? Is there some fat black ground wire that grounds the whole unit? I would check that out. Just toss'n that out there. I have not delt with this type stuff but I do nkow elevtronics a little and connectors can get corroded. May need to shine them up a little. Thoughts?

I'm going to replace the prom chip again with another new one...maybe another computer. It could be I just got some faulty ones. The parts guy I talked to said that PROM's don't normally go bad...but who knows. There are only two harnesses that plug into the computer and both look to be in great shape. When I drive it it runs great for awhile, maybe 10 miles, then begins to jerk when shifting into third and loses almost all power. I then shut the ignition off and it runs fine for awhile. graemlins/clonk.gif

I just read something about "idle air control valve" on the 2.8 and 3.1 engines being faulty. Could this be my problem??? I am pulling code 52 from my ECM, however, after reading this article, it sounds alot like my problem. It drives great for awhile, than like that it stalls or loses power. I pull over and shut the key off, start it back up, and it runs fine again. I'm about to throw a lit flare into her....HEEEELP!!! :confused:

Okay guys, check this out and tell me what you think...I pulled this off of another website..."The Calpak is that other, smaller, chip next to the eprom. The dealer has them. It contains part of the fuel control code.

1987 Chevy S-10 Blazer with 2.8L PART GM# 16051459

CODE 52

Trouble Code 52 indicates that the ECM sensed a fault with the CALPACK. The CALPACK is a plug-in module separate from the PROM, that contains preset calibrations used by the system during "limp home" (backup) mode. The ECM continuously checks for its presence while power is applied.

The conditions for setting this code are:

the ECM does not sense the CALPACK

Typical causes for this code include:

1) Incorrectly installed CALPACK module
2) Incorrect CALPACK module for this vehicle
3) Defective or incorrectly inserted PROM
4) Defective ECM
5) Missing, as in swapping computers and swapping the eprom but forgetting to swap calpak also!

When I got the re-manufactured ecm from NAPA...I replaced the PROM but they said nothing about a CALPAK!

graemlins/thumbsup.gif That sounds about right DOzER, good job on your search and good luck with your problem. graemlins/hurray.gif graemlins/beers.gif

The Trickster!!!!!!!!!!!!!!!!!!

Well...this morning I looked inside the computer...and sure enough, right next to the prom chip is a smaller terminal that accepts...you guessed it...the calpack chip. I ordered a new one today and hopefully after installing it my troubles will go away. I'll keep y'all updated!!! graemlins/clonk.gif