So this is a new one on me. Two days ago I was logging idle trims for my tuner and my o2 trims froze up. They locked up at 5.07 so no lows recorded. This was the 3rd map of the evening and the first two worked fine. When I blip the throttle they move for a minute then lock up again. I went back to the previous two maps that had just worked 30 minutes prior and those also froze up. I tried a new stock o2 sensor (I had a spare), tried another laptop, tried a map from 2 months ago, all of them lock up at 5.07 in EvoScan 2.7.0090 and 5.1994 in EvoScan 2.6. On a semi-tuned map the car still runs and pulls great so I'm not sure what exactly happened. I always reset the ECU before logging idle, not sure what else to try

 

Bump for help

 

Tried new scaling, new latency values, still getting nothing...help

 

I've also tried Mitsulogger now, to no avail

 

Thats interesting. Generally when the STFT stops moving its because the ECU has switched over to running in Open Loop. I have run across the issue of cars staying stuck in Open Loop during start up when closed loop usually engages after 15-30 seconds until you blip the throttle once and then its fine but it seems like your issue is different from this. What is your 2byte load at idle and have you altered the open loop tables at all?

 

I haven't...I can send you my ROM if that would help. My 2byte load is 50-54 at idle...here's the log. Thanks Jack!

 

Something else to note Jack is that it freezes at the same exact number each time. Is that number an indication of something or is it just random that it locks there each and every time?

 

Bump for some continued assistance. How can I tell if the car is always running open loop?

 

When I had this problem I would just stop the logger, restart it, and stab the gas pedal a bit.

If the o2 trim is maxed out, then you have an issue. Use the scalling guide to get it as close as possible.

 

The first thing you need to specify is which trims are freezing, your LTFT's (low/mid/high) or your STFT (O2 Sensor Feedback)? If the STFT is pegged full lean or full rich then your injector scaling needs to be adjusted.

 

im having the same exact problem pretty much. doesnt happen all the time. im going to try and replace the a/f sensor and see if it solves my problem

 

I posted a log, it is the STFT, when that is locked it does not allow low trims to record which causes my tuner not to be able to scale the injectors at idle. This is only locking up at idle.

Things I've tried and none of them worked -

Swapping to a 1 bar map sensor and tune
Changing the scaling/latency
Replacing the o2 sensor
Resetting ECU

Things I've tried that do work -

Blipping the throttle - note this only works until the next time it tried to record a low trim (every 6 minutes) and generally only works for 10-15 seconds. It is locking up at 5.07 which isn't max rich or lean.

This is also on the FIC2150's if that matters. We had tuned the car up to 33PSI at this point and it is running very strong but had an issue creep up where taking off from a stop the car pegs lean so it bogs for a split second then it's great and this ONLY happens when taking off from a dead stop so my tuner said let's double check the idle trims so he is using the STFT's but when those lock up so does the low trim

 

Also stabbing the gas pedal throws off the idle trims I thought. The whole idea is to not touch it period...at least I thought...

 

What is your formula for STFT in the logger? You guys removed the injector resistor pack with those injectors right?

 

Yep, resistor pack removed...formula is - (0.1953125*x)-25