prscarf

i saw somewhere on this board or the net a place which sells used ecm's or pcm's for approx. $30ea. does anybody know the side address.

Grumpy

It's more about developing connections, friends, and networking.

Most often Pick-U-Part type yards have the best prices on them, but in part because you have to do the work.

Grim Reaper

Scope out wrecking yards. Just don't ask for an "F-body" ECM. Ask for the "generic equivalent".

I.E. early 90s 3.1 V6 Cavalier/Sunbird (for SD) or late 80s 2.5 4 Cyl S10/S15 Truck (for MAF). They generally go for the cost of a "core charge" by GM around where I live ($50-75 for MAF and 75-90 for SD in Canadian Funds).

i see you are a Canadian, so forget about trying to get one for the US. By the time you paid the shipping/brokerage plus all the related taxes, it generally works out to be more expensive (and time consuming) than just picking it up at a local wrecking yard. Also, "returning" is a bitch (and incurs even more cost which you can't recover).

prscarf

i have a 91 truck pcm for my tbi i was wondering if a 94-95 truck pcm, which is also tbi, will work with my truck and wire harness. i would think it is the same except the new uses a 27c512chip and has different definition file.

Grim Reaper

No

prscarf

no why? a reason would be nice!

Grim Reaper

Different ECM/PCMs. ECMs/PCMs will only work for specific years/types of vehicles....nothing else. If you get lucky, you can cross-reference and find a similar ECM/PCM used in a another vehicle.

Think about it, if it uses a different Memcal, then how in the hell would it work? It's like pulling a ECM/PCM from a 93 F-body and expecting it to work on a 92. Hell they even use the same sized Memcal (27C256).

Pull your ECM, get the proper numbers from the sticker and go to a wrecking yard to get the right PCM. You can't just mix and match them.

And yes, different ECM/PCMs cost different sums of money. The older ECM/PCMs tend to be the cheaper ones (because they are the least sophisticated and get the lowest core charge from GM). Newer, more sophisticated PCM/ECMs cost more from a wrecking yard just because GM has a higher core charge (and the cost is far more expensive from GM).

prscarf

Think about it, if it uses a different Memcal, then how in the hell would it work? It's like pulling a ECM/PCM from a 93 F-body and expecting it to work on a 92. Hell they even use the same sized Memcal (27C256).


i am not trying to **** you off, just trying to understand the system and i may not be the sharpest knife in the kitchen but try to see my point of your first answer (no).

what i am trying to do is use the complete pcm c/w with its memcal. i want the newer programming functions that the new pcm provides. if you look at my 91 truck tbi and the new 94-85tbi they both have all the same sensors and controls to the engine. i will not use my old memcal at all, remove my pcm and install the newer pcm then program the new memcal with the newer editor. hope this clears up my question.

Grim Reaper

Well, see my point...you said none of this in your post until now.

Initially, it looked liked you were just trying to swap one ECM/PCM for another without realizing you are going to have to look at a lot of other things (like wiring/pinning the harness).

When you only give us part of what you are trying to do, you will always get the short answer because the short answer is still no.

The first problem I foresee is the tranny. The later model supports the 4L60E, yours doesn't have one. You are going to need to do a lot of research, get wiring diagrams etc. It is probably possible to "graph" the 94/95 PCM but it won't be a "plug n' play".

But if you want "detailed answers", don't be lazy and only type a short "can I swap a 94/95 PCM in my 91 Truck" because the you will always get a short answer. Always explain FULLY what you do, you get much better answers.

But, also, please understand that this is a Thirdgen Site and while a few us may have some knowledge of the later ECMs/PCMs, most do not have a detailed knowledge. You are most likely going to have to do a lot of "self research" and get wiring diagrams.

Grim Reaper

I'm sorry to lecture, but if you look at your FIRST post, it was about "a $30 ECM". Then it was about a swap.

What you've done is wasted mine and Bruce's time because you gave us a VERY SMALL PART of what you are really doing. First, we are ALWAYS going to assume you are talking about a 3rd Gen, unless told differently.

Some people think that "if I say it is for a non-thirdgen that no one will respond". Well, the reality its, this is a Thirdgen Site and probably the reason no one responded is because on one really knew the specific answer to your car.

BUT PLEASE, do be courteous to the people and ALWAYS tell them fully what you are doing. Re-read your posts and I think you must agree that you were really unclear/evasive in what you asked and most of the answers I gave were a complete waste of my time because it related to something different.

prscarf

sorry, no flame intented. let try again, mine is a pcm and it does have the computor tranny but not the 4l60e but the 4l80e. the new pcm support my tranny as far as i understand. below is what my engine combo is and all the particulars.

also, i didn't mean i have a $30 def. but purchase price 30 dollars.
sorry.


91 chevy 4x4 sbc 383 stroker, 64cc 23deg trickflow alum.heads c/w weiand
> excelerator single plane, adapter, cam is an extreme 4x4 comp. Cam.
12-235-2
> grind ( .447/.462 lift, duration 210 218 lift @50, 111 lobe separation) .
> unit has hypr. Flattop floating pistons, eagle cast crank, 5.7eagle rods,
> bal.to 0.5grams, 10.2:1 comp. Headers c/w 2.5" flowmaster exhaust.
16147060
> pcm, $85def
> 454tbi 80lbinjectors
4l80e tranny