ECM fried, ok to use the wrong one?
 

Well i've been working on my car, 305-350 TPI swap. I'm wondering if I run a 305 computer if it would hurt the motor in any way. I know the performance would be off. I have a 350 ecm installed but it's fried, won't even start with it and still have the functioning 305 ecm and the car fires right up with it installed.

This car's been sitting for a few years now and I just want to DRIVE it again. Also wondering if it's possible to just pull the memcal from the 350 ecm and just toss it in the working 305 ecm and have an instant working 350 ecm. That seems too easy and inexpensive to work with my luck.

Re: ECM fried, ok to use the wrong one?
 

As long as both ECMs are the same, IE 165 ECM, then you can just pull the 350 prom and put it in the good ecm. If the car doesnt start then you know the prom is shot...

Re: ECM fried, ok to use the wrong one?
 

if the memcal for the 350 is from 89 it would contain vats and would need to be bypassed. You didn't post the ecm service number? The ecm for maf service numbers are the same ecm 77-7165 ,01227165, 16198259, 16198445 all the same ecm for tpi maf.The memcal is the calibration you can post the letters on the memcal for identification.

Re: ECM fried, ok to use the wrong one?
 

I'm thinking it is '88 or older. It did run with this ecm at one point, but it started kind of tweeking on me and throwing SES lights that never flashed during startup or blinked a service code. It would do this randomly. Then it did it all the time and ran TERRIBLE and was hard to start. Now it won't even start.

Then I plugged in the cars original ECM just to help diagnose and she fired up almost instantly.

Any idea if the problem lies in the memcal or in the ecm itself?

Re: ECM fried, ok to use the wrong one?
 

If the old ecm is non responsive to even going into diagnostic mode and the correct memcal in stalled correctly sounds like a bad ecm.

Re: ECM fried, ok to use the wrong one?
 

Thanks. I'll try swapping memcals to the known working ecm and post my results. Unless there are any better suggestions?

Re: ECM fried, ok to use the wrong one?
 

you may have other issues as well, ignition timing stale fuel stuck 22#hr injectors for sitting you have not indicated what all that has been done.

Re: ECM fried, ok to use the wrong one?
 

I didn't get super specific just because I'm 99% sure most of my issues are related to the ecm's functionability. When you plug in that 305 ecm, the car runs fine.

If it helps I'm happy to add more info. I bought the car as someones hack-job 350 swap, what I do know about the setup is anything I can see visually and things I've done to it. These are:

350 swap itself- 2 piece rear main block with old style heads
Original 305 TPI setup
Ford Racing 24# Injectors (don't ask me why fords, but they work!)
350 Knock Sensor
350 spark control module
Adj. FPR
Lord knows what cam is in there

frankly I wish they would've left it a stock 305 TPI, odds are any power they picked up adding 45ci was probably lost in goofy tuning and the reversion from roller lifters to hydr. It does look cool with the old school valve covers though.