Running Lean

[big_bertha]

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?

[decipha]

No

Sounds like you do not have a ccd distributor that the ecu is trying to control maybe.

what is the ecu hardware code?

[big_bertha]

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?

[big_bertha]

After some fortuitous googling, looks like VEX1 has the same hardware code...do hardware codes map 1:1 with strategies? I.E. can I use the VEX1 def to probe/tune this ECU?

[wwhite]

do hardware codes map 1:1 with strategies? I.E. can I use the VEX1 def to probe/tune this ECU?

Sort of. Any .bin from same hardware code should work on same hardware, key word should.
You must use the same .bin as for what the .def was created for.

If your using VEX1 def, you must use VEX1.bin. It is possible DEX0.bin will need a different definition.

[big_bertha]

If your using VEX1 def, you must use VEX1.bin. It is possible DEX0.bin will need a different definition.

Can you dump a bin from an ECU with a quarterhorse if you have the correct def? Or at least get real time ECU values without the corresponding bin on your laptop?

[decipha]

you don't need a definition to read the bin simply follow the steps outlined in the getting startup write up to read the tune out

you need to have the correct bin and adx in order to put the patch code in the tune to log correctly.

Read the tune file and post it here someone will be able to tell you if its the same strategy or not.

[big_bertha]

Thanks for the help. Attached is my attempted read of the calibration.

Something's weird though, with the quarterhorse plugged in the CEL is on and idle oscillates around 500 RPM. With key on engine off fuel pump runs continuously and I can't get the self test to run or error codes displayed...

[big_bertha]

not seeing any values while attempting datalogging either, not even garbage, and the status lights are green in binary editor.

[big_bertha]

ah, I see the continuous fuel pump running is addressed in getting started, will try cleaning J3 contacts again.