A little help needed with 1st drive on Jester's plug n' play ECU, logs attached.

[Ben_Pow!!]

idle & cruise logs.zip

Jester's plug n' play, 1st gen fed spec TT.
1000cc denso injectors
482 montero maf

I'm trying to figure out what's going on with my car. Injector scale/latency adjustment got it to idle okay, a little rich, 02's not cycling, but running good. I figured I'd take it out for a drive and let the low/mid trims adjust. It started off driving smooth for about 1/8 mile, then it slowly leaned out completely. I'd give it more throttle and it would just rapidly pop (backfire), but not loud. I had to drive very slowly and light on the throttle to get back home. I gave a couple hard throttle pushes to get it out of closed loop and it seemed to straighten out, however there was absolutely no power. Looking at my logs, it appears that something is wrong with my narrowband 02's. The numbers are everywhere. Can someone take a look at my logs and see if something jumps out at them as abnormal? I'm going to double check ignition and valve timing and check for boost leaks, compression test and check spark plugs this weekend. Anything else I should try or check?

-Mike

[Greg E]

Can't download the file using my phone. However, can you verify something for me? Did you change the intake tables over for that MAF? If so, does your boost gauge move at all or does it stay at the bottom with the engine running and driving?

[Ben_Pow!!]

Can't download the file using my phone. However, can you verify something for me? Did you change the intake tables over for that MAF? If so, does your boost gauge move at all or does it stay at the bottom with the engine running and driving?

Yes, I updated the intake tables according to the "how to tune your 3 s using chrome" tutorial, for the Evo maf. I couldn't find the scaling for the montero, but two people verified using the evo scaling works fine. Also, I have the wiring to the maf rigged temporarily until the plug n play adapter is shipped. I've read that it's a direct conversion as far as the wiring goes... same number of wires, in the same order, that's the way they are. On the log, airflow seems to be showing correctly. I will double check when I get home and see about the boost gauge. I previously was using the maft pro using only the wideband for open/closed loop driving, so I've had my stock 02's out for a long long time. I installed the oem 02's (very old), and later found two aftermarket ones laying around. I'm thinking the stock 02's may have went bad back in the day now that I think of it, I'm going to swap to the new sensors and see if that helps. Back when I used to log narrowband 02's, I don't recall them ever being this sporadic. Another clue is that the fuel trim mid shows the front at 12.5 correction, and rear at -12.5. Thank you for the response!
-Mike

[Greg E]

Ah yeah your pin out dip switches may not be setup properly for your car.

[Ben_Pow!!]

Okay, the ECU is still laying on the passenger floor. I can pop the cover and take a look. Is there a link or thread somewhere which has the dip configurations I can check against?

[Greg E]

Pretty sure Adam put direction up on the chrome ECU website.

[Jimvr4]

I think the best thing is to run a log of the front and rear primary 02 sensors. You can log them to the screen. The harness connectors are right near the dipstick and on top of the front valve cover. Unplug just the front one and verify it stops logging it. Then do the same for the rear. If you unplug the front one and it stops logging the rear one you found your problem.

[Ben_Pow!!]

Jumper setup: The 91-93 US VR4 PNP ECU can reverse the primary O2 sensors by changing the jumpers.

Stock setup the jumpers should be horizontal with the plug down. If the jumpers are vertical this switches the O2s.

This is the only thing I could find, not dip switch though.

[Ben_Pow!!]

Okay, will try that. just curious though, why does the ecu care if the 02's are reversed?

[sublime_whatigo]

I assume the jumpers are what Greg is referring to. You said your fuel trims are pegged, 1 rich and 1 lean. If they are reversed they would be correcting for the wrong bank, the more it tries to correct the worse it gets.