The TPS checks out good, unfortunately.

 

Well, after finally seeing Justin's car I just have to say I cannot believe he hasn't killed someone yet. The car is beautiful inside and out and short of a few hundred gremlins is one of the best examples of a 3rd gen I have ever seen. It must be a lot like dating a supermodel who doesn't like to kiss



The surging is as big a problem as I have ever encountered. It is identical to a MAP sensor issue EXCEPT that the map sensor seems to work above idle. In other words, at idle the sensor output seems like a flatline, under throttle however, the sensor appears to behave somewhat normally.



Of course it could be the idle air control assy, or a bad throttle body, or a bad idle air bypass screw etc. etc. etc.



We did manage to retune for safety and driveability above idle, but no amount of messing with the idle cells (richer, leaner, timing etc) made a damn bit of difference. I am guessing a mechanical problem (including physcially screwed up sensors) somewhere. Any help or suggestions are appreciated.

 

Dude, just unplug ur ISC and tune your idle manually with the screws.. take the computer out of the equation.. make sure you don't have any leaks... cuz it sure sounds like a vacuum leak.. Cuz ur car can still pull good but idle like **** if there is a teeny tiny leak.. check all your injectors, LIM to engine, LIM to UIM, and all nipples.

 

One of the judges at the last AutoX heard my car warming up and asked what my cam duration was.

 

I've done that. No better. I actually tried that FIRST.. When that didn't work, I tried to tune it out with the ISC plugged in but the results are nearly identical. Only difference between the two is when the ISC is plugged in and I start the car, it shoots straight to 3000 RPM.



I'm going to go back over the car for vacuum leaks.. But I'm not even sure where to look anymore. I actually HOPE I find one.



Jeff, thanks for the compliments! And again, thanks a bunch for all the help! Hopefully I can get this thing sorted out and we can see what this car can do.

 

have you tried to reset your ecu?

 

Yep. I've even tried other ECU's.

 

easiest way to check a vac leak is with propane or smoke. If you use propane the car will idle higher once it sucks it in.

 

Done. I had a little one at the boost controller.. Fixed it, although I don't think it was a contributor.. Idle is still at 1400RPM.. However, It hasn't been surging lately.. Been driving it for the past 2 days and it hasn't done it. Course, I haven't hit 87C either...

 

well now just adjust the screws