car suddenly wont start - never ran great anyway, esp. cold, now cranks, but won't st

cre · 04-01-2011, 11:23 PM

Heh, yeah those multipliers can be a real bitch. lol. It's okay, I'm sure I've done it.

A bad TPS wouldn't cause significant issues with the operation of the engine... it's just a trim sensor. Worst case scenario you have a poor idle, fuel economy gets a little worse and your throttle response gets a little sloppy. You can actually disconnect the TPS and should be able to drive without noticing a huge difference.

Measuring resistance of the TPS isn't as reliable as measuring the actual voltage at the ECU's VTA pin. Should be ~.5v throttle closed and 3.5v throttle wide open. I remember from tuning these cars that the voltage should not exceed 3.48v at WOT. Vc should be at about 5v (around 4.8v measured at any sensor location).

I thought I already covered this but that must've been in another thread.

04-01-2011, 11:23 PM	#31
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Heh, yeah those multipliers can be a real bitch. lol. It's okay, I'm sure I've done it. A bad TPS wouldn't cause significant issues with the operation of the engine... it's just a trim sensor. Worst case scenario you have a poor idle, fuel economy gets a little worse and your throttle response gets a little sloppy. You can actually disconnect the TPS and should be able to drive without noticing a huge difference. Measuring resistance of the TPS isn't as reliable as measuring the actual voltage at the ECU's VTA pin. Should be ~.5v throttle closed and 3.5v throttle wide open. I remember from tuning these cars that the voltage should not exceed 3.48v at WOT. Vc should be at about 5v (around 4.8v measured at any sensor location). I thought I already covered this but that must've been in another thread. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

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