Seems to be running in open loop

[KevinsZ28]

I have a 94 Z28 with SpeedPro that I have somewhat tuned, at least good enough to cruise around in. I was at a car show waiting to get out onto the street, idleing for about 30 minutes, when the car starts to Idle at about 1500 rpm for about 5 seconds, then it drops to about 500 rpm and about dies. I didn't have my laptop hooked up to the SpeedPro to see what was going on, but I just gave the car a little gas to keep it running. Finally I got out on the steet and gave it quite a bit of gas to do a burnout and it seemed like the throttle was stuck at 4000 rpm. I pulled off the side of the road, turned the car off, jumped out and check the throttle and it wasn't stuck at all, jumped back in the car and it started up and idled okay. I finally got the laptop hooked up to the car and I noticed that the speedpro is not applying any corrections, it is like the car is running in open loop. I have tried to reload the tuning program again, clicked the run in closed loop button off and on again, and nothing happens. I know the car is now running very rich, could I have fouled the o2 sensor??? If so, can you clean it?? Any other suggestions as to what might be going on?? All the other sensors are working fine, just no corrections to the AF ratios. Any help will be appreciated.

Kevin Thompson

 

[norbs]

Open or closed loop should not effect the idle rpm much at all, i suspect the iac driver has gone bad in the box, or your iac in your car is sticking. If there's any afterstart enrichment going on it wont go in to closed loop or if you hig and closed loop limits are set wrong it wont go into open loop either. Try setting the low rpm and high rpm at 800 rpm closed loop set points to see if that helps. I would take all power off the ecu and put a new program in also, it may have gone corrupt somehow.

 

[KevinsZ28]

Right now my low RPM is set at 550 and the high RPM is at 600 RPM. The car was runing fine one minute, then like crap the next. Is it possible to foul out the 02 sensor. Anyone have any ideas? I am 3 hours from home at a friends house and need to get home tomorrow. I can drive the car, but is sure sucks whenever I accelerate or decelerate, I can smell the raw fuel being dumped into the car.

 

[norbs]

Press ,f9 i think or f10 while running if in the menu shows any of the uego parameters in red i would would say the sensor is toast or has a bad connection.. You will see the o2 correction locked at 0% also

 

[bobc455]

Might want to log the IAC also.

-Bob C.