My tps sensor is going the wrong way down a one way street!!

[bluto5]

Soo.. here we go again. 1 by 1 problems pop up and so they fall before my trusty wrench set and snap-on vantage dmm.(dmm of the gods /bow)

 

After putting about 200m (highway miles) on the rx after getting it running reasonably well(idles and drives fine, just no hard accel.), I had a chance to get it back into the shop tonight to troubleshoot the wot(or even heavy throttle.) stumble.

 

It wasnt horrible, it just didnt pull if I put my foot to the floor. gawd I hope I havent reinjured my motor with some lean under boost detonation..

 

My fruitin tps sense wire goes from 5v+ at closed throttle to 3.5v at wot. Ok, thats diffrent. As long as I havent hurt the motor all will be forgivin. Compression test to come. It sounds fine but I couldnt hear the dead cyl when I bought the car either. always sounds more or less like a singer sewing machine.

 

There is a forecast of possible snow and sleet this weekend. I hope I can get a new sensor by then... of course I also need a new blower motor resistor and blower motor. Oh yea, my brakes are also threatining to mutiny, the left rear is the loudest complainer( I was hoping they would hold out till I could swap to 5lug.)

 

All in all I am content with the progress, each trip back to the shop knocks a few more tidbits off the to-do list. The fun stuff like IC and exhaust are getting closer too.

 

Sam

[ple1ades]

check this out I still have a hesitation when I am WOT over 5000 rpms but I think its the fact I dont have a rear o2 sensor.

 

http://www.ultimatesubaru.org/forum/showthread.php?t=56613

[Forkspear]

I dont think it is the O2 sensor. The computer ignores the O2 sensor and goes into open loop when you are WOT.

[Cougar]

I think the TPS voltage for WOT should be 0.5 volts to around 1.8 volts, not 3.5 volts. It sounds like the TPS is not adjusted correctly and you are not getting the right amount of fuel to the engine for that amount of throttle position.

[bluto5]

tps voltage at wot should be 5.0v and .5 at closed throttle.

Thats what the haynes and vantage say anyway.

 

Sam

[silverhelme]

Be sure you are checking the right wire for voltage. Your vantage should tell you which one to back probe. It sounds like you are checking 5v reference wire from the computer not the wire that goes back. I have the scanner and have access to a vantage ( as well as the newer scanner if needed ) and work with them on a steady basis. If you are getting that kind of voltage on the correct wire something is obviously wrong with your TPS.