ECM issues???

[mean_maverick]

doing an EFI swap on a 5.0 on a Maverick (of all things, lol) and need some advice. i got everything up and running but im having some idling issues and timing issues. maybe they're connected, maybe not.

but im running an '89 mass air harness, 94-95 intake and an ECM from a 91 Cougar that had a 5.0 HO vin code:T. this should work together and be friendly, correct?

i have set the base timing with spout removed at 12 degrees btdc, factory recommends 10 but i always bump it a little.

the warmer the car gets, the elss it wants to idle. with the spout in, it will not rev above 3K but with it removed, it doesnt advance correctly.


im looking for any insight.... anything! thanks in advance guys!

 

[jrichker]

See the "Surging Idle Checklist for help with all your idle/stall problems. Everything you need to find and fix idle problems is in there.

The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.