pcm goes to crap...

[ZOHAN]

So does anyone know anything about the internals of a 94/95 pcm, and what actually goes out when they decide to quit? Just wondering if its possible to fix, since you can buy a reman one... so what's it take, cause it must be possible...?

[bigtoyz]

http://www.madtuner.com/

I think this is the same guy who fixed mine when I tried to socket mine, Ion is his name if I remember correctly. He is good at it and fast turn around.

[ZOHAN]

So madtuner stopped fixing them. Anyone know of anyone else?

Making you silky smooth...

[Sapper]

The 4 processor chips go out in them. Ion also did mine way back when and i had the replacable chips installed. That way, 4 new chips are only $30. Split cases, plug in new chips, reseal cases, load your tune back in and you're done.

BTW, I have it for sale. It's out of my 94 Impala SS. It's current tune is for a hotcam and other mods. I have 24x so I have no need for it.

[waggl1]

I have an obdI pcm for sale it was setup for a 383 with 30# injectors and a cam

[ZOHAN]

Just looking to have a few repaired for the time being. For future reference, how much are you both wanting for them?

Making you silky smooth...

[bobdec]

Zohan, if they 'brick' when loading a tune. Here's what happens... The 128K of basic code to run the PCM -AND- the tune data must be erased from flash memory prior to starting the code load. These old PCM's only had 64K chips available so they split the basic software between two 64K chips and if the code load fails due to a connection, laptop, etc problem you then have 1 or 2 messed up chips, similar to bad BIOS code on a laptop or PC, and the PCM is a brick. The base code can not be re-loaded via the ALDL cable as the PCM can't boot up. You have to remove (un-solder) one or both of the 64K chip(s) and use a burner to re-load them. The repairers removed the chips then add a pluggable socket, burn good chips and plug them in. With the pluggable socket it's easier to then just get re-burned chips and do it yourself if it happens again. Only a couple of people did repairs and they have faded out. With used PCM going for $50-90.00 and cost of labor going up, requiring special soldering tools & skills it's hard to find someone that will fix them.
However if the PCM is defective due to a circuit, driver, sensor input failure (very rare) then basically no one fixes those, it's a throwaway, maybe in future years as they become scarce things may change.