Hey guys, another day, another post. I am still trying to get my JDM S4 TII to run right. It is in a 85 GSL-SE. Belows are my symptoms and what I have found so far.

Symptoms:
Car starts, runs fine, idles about 750rpm. Will rev great all the way to 6000RPM the first time I give it gas. After I let it return to idle and try again, the engine seems to bog down at 2000RPM and will rev higher, but the RPM will fluctuate by 100RPMs with the throttle held steady.

Voltage Readings:
TPS Green/Red wire at idle with switch in "ON" position and when first started: 1V
TPS Green/Red at idle after reving once: .85V

TPS White/Black power wire at idle with switch in "ON"position and when first started: 4.96V
TPS White/Black at idle after reving once: 4.86V

Can any one tell me why this voltage would be changing. I have two S4 TII ECUs and they both do the same thing. I hooked up the check lights for the TPS and one light comes on. I also checked for error codes and found none.

 

When I had a similar problem, it ended up being my AFM.

 

Hopefully thats not it. I just paid close to a $100 for my AFM. Thanks for the tip. Any other ideas.

 

I checked the voltages from the AFM at the ECU and they seem to checkout. I'm not sure what to do now.

 

my TII doesnt run either! lets start a club

-Ben Martin

 

Oh it runs. Just really crappy. But I can still lay down some rubber.

 

i would check you cats they could be clogged how often in a time period have tried this....it sounds like you have covered all of the typical problems so you might just want to check it out just in case

 

Thanks for the tip, but I am running an open downpipe.

 

how's your fuel filter? any vaccume leaks or intercooler leaks?

 

fuel filter is new. haven't found any leaks so far.