EFIDynoTuning Forum

SMD-221

One of my attempted fixes was to swap from the stock push start (grey) ICM to the black CCD module, rerouting wire #4 to pin #4. Same behavior. Distributor is OEM (same behavior on original distro and OEM replacement, ruling out PIP).

Note that the timing does consistently advance from base by around 10 deg for a moment when throttle is closed (idle remains high for a couple seconds). Presumably this is as designed and indicates that the ECU is able to adjust timing?

Summary: would a 302 computer on a 351w engine cause a lean condition and no timing advance?

I have a 1990 Bronco with a 351w and 36# injectors and I recently completed a MAF swap using a 1994 computer, all stock otherwise. I've been trying to diagnose a persistent lean condition. Wideband reads 16-17+ while revving in neutral and accelerating, and the ECU refuses to advance timing beyond base. The ECU does momentarily advance timing on throttle close consistently, and very briefly with RPM after starting, so I don't believe this to be a hardware problem.

Long story short, I've been through everything (distributor, ICM, fuel pump, pressure regulator, wiring harness, etc). MAF sensor is ostensibly calibrated for the 36# injectors. Now, getting to my question, I recently discovered that the ECU that came with the kit (F4TF-12A650-BEA, calibration DIX0) is for a 302. Despite common forum wisdom regarding compatibility, could this ECU mismatch be the source of my problem? I've browsed the tuning docs on this site (fantastic resource, btw) and I understand that the ECU will yank timing under certain conditions, but in my case I'm missing about 20-25deg of timing at ~3000 RPM...

Any advice is greatly appreciated, thanks.

P.S. I have a quarterhorse, but from what I can tell the strategy definition for this calibration (DIX0) is not available. Is that something I could get with a premium membership?