SR20DET running really rich

[MattLauer]

I've beefing having this issue with my car for a while but I'm finally at the end of my rope so I consulting you guys. I have an '91 S13 with an S13 SR20DET installed. Almost a year ago the car was running fine and about a month later I started running very rich and wouldn't let me connect via Consult. I'm finally getting back to messing with the car and after trying various things I'm able to at least connect to the car with NISTUNE.

I'll fill can fill in some more details tomorrow but I wanted to get my video uploaded before I get to bed. The video linked below is my car idling in my garage after it had been on for maybe 10 seconds. As far as I can tell, the tune running should be the stock one. Both the injectors and MAF are stock. I know very little about tuning and have nothing to compare my car too so I have no idea what doesn't look right in the video.

https://youtu.be/ngtm1BsQ4xc

[Matt]

Can you post the tune and log file?

[MattLauer]

Matt, is love to get you those files but my car is acting up again and I can't connect to it with my laptop. I'm at my wits end with this car.

[Matt]

If you cannot connect (when engine not running) then check over your board installation. Sounds like the ECU is limp mode

Who installed the board? Check over soldering for an intermittent connection. Otherwise you could send the ECU here for checking

[MattLauer]

I switched back to my factory ECU and it's still not running quite right. I don't know if it's the car or the ECU. I did manage to get a 15 minute log file of the car from a cold start to an 80 degree celsius idle. The CSV is attached. About 5 minutes in I was putting the metal clip on the MAF and it died. I stopped logging, put the clip on, and continued logging from there.

[danielp11]

i have had a problem with consult connectivity before and it turned out to be the factory consult connector that runs into the stock harness was the problem, for a more stable connection you can go the wreckers yard and cut another consult connector and loom from any 90s nissan and hard wire it at the ecu harness connector. this usually gives a much better connection as the wiring is then much shorter and less susceptible to noise and interference.
hope this helps with your consult issues.

[Matt]

Cannot see much from the log without the AFRs. If you do another log make sure you record in stream mode and with a wideband connected

If you are using standard MAF/injectors and same problem on both ECUs then something else like MAF issue or airleak may be causing the problem

[MattLauer]

It is a completely stock setup. When I'm able to get Nistune connected with the Nistune board installed it runs the same, as far as I can remember. When the Nistune board is in I can rarely connect. I've completely replaced the engine harness with a Wiring Specialties harness so I know that's not the issue. I've also swapped various MAFS and O2 sensors. I wish I had a third ECU to test with but I'm trying to avoid buying another and I don't know anyone local with an S13 SR.

[Matt]

Do you have the connectivity issues (in tuner mode) with both ECUs or just the one with the board fitted?

Does the ECU with the board fitted enter limp mode at all when running (unable to connect at all?)

Do you have connectivity issues when engine not running, or only engine running?

[MattLauer]

I have connection issues with both ECUs only when the Nistune board is installed. When I move the jumper and remove the board I am able to connect just fine. I sent my S13 Blacktop ECU with Nistune board fitted to AutoVaughn a few months ago for him to test. He replaced the Nistune board even though it seemed fine to him and said everything ran fine on his setup. I don't know what testing he did to see if it was working.

When the Nistune board is installed I think the car is usually in limp mode. The car only primes for maybe a second instead of the usual 8 or so. I also noticed that with the Blacktop ECU the fuel pump relay will sometimes make an odd series of clicks whereas the redtop ECU will sound normal but still only prime for a second.

Having the engine running or not doesn't seem to make a difference with connectivity from what I have seen

[Matt]

Okay did you want to post the ECU to me to check out? I can go over the installation and run it in my vehicle (via patch harness also)

Shoot me an email info[at]nistune.com. Return postage is $45AUD if using express post return to USA