Thought you were gunna disconnect the tach and see if the problem went away?

 

problem fixed! i hope...



hotblue02, that was going to be the next thing to try if the problems persisted. the only reason i avoided it at first is because it would involve de-soldering + wrapping my existing connection. sometimes i'm far too lazy for my own good.







anyway, check out the sensors that came out of the car! the crank angle sensor (right) had a light coating of liquid oil on it, but the cam angle sensor (left) is caked with old, burnt oil. i'm not surprised/don't blame it for acting up. i've installed new replacement sensors and taken the car for a ~30 minute test drive, through an OBD cycle and just general testing and the car didn't act up at all. the problem is fixed! yay!



although it did exhibit one of its old tricks of occasionally dropping the rev limit to 5500. it seems to do this after long periods of light throttle cruise, but not all the time. turning the car off/different running temps seem to have nothing to do with it. like you can bounce off the low limiter, then 30 seconds later it will be back to normal. i have -NO- idea what this is, the car has been doing it ever since its been swapped. i have replaced the 02 sensor to no effect. i won't drag this thread on because you guys have given me so much help already, but if there is an obvious fix to this, please do share.

 

Test your TPS?

 

okay, just tested the TPS. WOT voltage was only 4.33 volts, as opposed to the hmaservice reccommended 'about 4.75 volts'. it is getting a full 5 volts from the ecm, btw.



i'll go to the wrecker's yard on monday and find a decent TPS and see if it fixes the problem. i'll report back with progress once it has been replaced. cheers so much for your help everyone, electronics kick my ass frequently so your insight is really appreciated. +1 all round :3



*EDIT* It turns out i had a spare TPS from my old alpha. I swapped the units over and re-tested. The other TPS also reads exactly 4.33 volts, so i don't think the TPS is at fault. Both units had a smooth voltage progression from closed to WOT.

 

Smooth voltage progression is nice, but what happens when you tap on it (knuckle, not hammer) and try to twist the housing?



You also might be fighting a loose ground connection on something important. Intermittent problems are the worst.

 

yeah. i think i'll keep a multimeter + list of target voltages for the different sensors in the car. that way, if it does act up i'll be able to catch it.



maybe if it was the TPS itself the problem will be solved. i've got the alpha unit on there, so i'll see how the car likes that.

 

(fingers crossed) here's hoping