I suspect that my factory ECM may be having issues. I want to get another unit but am not sure if I have to stay with a 1988 or if I can include a 1989 in my search options.

I do have a PCMfor less PROM, a new 355 TPI ZZ4 based engine going in soon; a completely upgraded intake system with no 9th injector- enlarged airbox-ram air boxes, mega ported & port matched TPI parts, etc.

I DO NOT know yet how to program my own PROMs, but I'm close to jumping in. I also need to know if I need to stick with the 350 TPI ECM or if I can switch my PCMforLess PROM into a 305 box? I could sure use some precise guidance on this. Thank-You, Nitro-Nicky

 

TPI ECMs from '86 through '89 are all the same. The MEMCAL (see sticky) will vary. Usually another ECM is obtained and the MEMCAL swapped from the original to the new ECM.

The original OEM number for the ECM is: 1227165. Although there are (IIRC) two other numbers for the same ECM today.

RBob.

 

If I'm suspecting possible trouble from my ECM and I pull one out of a wrecked camaro for my 88 A/T 350 Iroc; should I ever suspect that the Memcal could be acting 'the bad'?

Then it would be either an '88 or an '89 L98 PROM that would work in place of my PCMforLess PROM so I could double check and verify that the ECM, the Memcal, and my PROM are all working correctly or not- If I'm understanding this.

So then, my best bed would actually be to find an 89 L98 ECM with all it's various parts for a straight over plug in and test the results against my current setup???? I'm a little slow in grasping this; feel free to get a laugh at my naivity just as long as you eventually throw me the bone of a precise answer! Nitro

 

The '7165 ECMs have reliability issues. Tap on the case while the engine is running. If it stumbles when tapping on the case, the ECM is probably bad.

A stock '89 MEMCAL will have VATs, so the engine won't start/run when used in a '86 - '88 MY vehicle. So will need to look for an '88 ECM from a l98 f-body.

RBob.

 

Wow Rob, You've almost hit 10,000 posts! I'm impressed!!

Thanks for stepping up and lending me a hand. It is lifting a big chunk of gnawing stress off my back. Hopefully there'll be a Karmic return for ya-
Nitro-Nicky

 

From 86 up to around 1989 you should have the 12277165 ECM. The later model years had a 1227737 ECM as these were speed density cars. I'm not positive of the year in which speed density was completely phased in. I want to say 1991 but dont quote me on that. Your car should have the 165 ECM installed as it should be a mass air car.