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As long as I have an ECM from a 93 5.7 LT1 (car in sig), can I use an ECU from a 93 3.4 v6 F-body?
Or what other vehicles' ECU's would work or are the same?
Is there a certain part number on ECU's that I need to be aware of?
I think my my current ECM or ECU (or both) might have an issue (thread here). I have an extra ECM for a 93 LT1 I could plug in to test. See included picture to make sure what I’m calling an “ECM” is in fact that.
I could plug my extra ECM into the my car’s current ECU to see if that helps my problem, but I’ve heard if the ECU is bad, it can fry the ECM. Is that true?
So, I wanted to try both a different ECM and ECU, and if that’s not my problem, having extras can’t hurt. But there aren’t a lot of 93 LT1 ECU boxes (what I’m calling the thing ECM plugs into) on eBay, and they’re really expensive. But there are a lot of 3.4 ECU’s for cheap
But I think I’m misinformed that the GM ECU’s were compatible with multiple vehicles and the ECM was what was engine specific.
The picture is the PROM Memcal…. that contains the program required to operate the engine. That is not the ECM. That plugs into the Engine Control Module (ECM in “GM speak”). It is highly unlikely the V6 ECM would connect properly to the LT1. The inputs and outputs are significantly different, the V6 uses a multi-coil waste spark ignition, has cam and crank position inputs which do not match the high and low res cam position inputs from the Opti, etc., etc.
And it would be absolutely impossible to run a 93 LT1 with the Memcal from the V6.
Do you think I can test this extra LT1 Memcal on my car and see if it makes a difference, or do you think I could ruin it if the actual ECM/ECU has some issue?
If both memcals are from a 1993 LT1, (and possibly with matching transmission type) it shouldn’t hurt to swap the spare in. Depends on whether it is a stock factory part, or one that has been “burned” by an aftermarket source for a high performance application. If a “custom” tune, the engine might run really poorly, to the extent it might supply way too much fuel for example. The trans shouldn’t be a big issue, but with an auto trans I believe there is a torque converter lockup signal, while the manual trans might have a reverse lockout. The 94 and up PCM's are more involved with the operation of the transmission (both auto and manual). Hence calling them Powertrain Control Module.
I was told it was from a stock car, but I didn't know there were custom ones. I was under the impression tuning was done through piggy back chips on 92-93 cars (I've been under a several wrong impressions in this thread ), but do vaguely remember those Hypertech junk chips people were buying instead of custom tunes back in the day.
I'll see what happens when I swap this thing in...next time it's not too cold to tinker in the garage.
), but do vaguely remember those Hypertech junk chips people were buying instead of custom tunes back in the day. 