I just installed a new engine into my car and we used the new throttle body from the new engine. Actually the engine is used. It's a D16Y7 with roughly 171,000 Kms.

Anyways, We got the engine in and everything is all good, Except for the the fact that at Idle the RPM's Bouncing From 1000 - 2000 and back again. It does this over and over and over with no sign of it stopping. Now were fairly certain that it's a bad TPS sensor that came along with the new engine but were not 100% sure.

I've done lots of Searching and Wrote down everything I could find about the TPS. Including the Proper Readings, and such. I just wanna make sure that the TPS is the problem before I go ripping it all apart.

Do I need to Remove the throttle body to get at it? And how exactly Do I Adjust it. I've found info on removing it and checking it but not Adjusting it.

Any info or Suggestions will be greatly appreciated.

 

does it run the same when u unplg it? u can test it pretty easily on the car just use an ohm meter across 2 of the wires( not sure what 2 ) and you should get a reading that changes when u open the throttle make sure theres no opens of high resistence spots im not sure what the specs are for it. u might be able to search 4 that or search potentiometer testing or somethin. ???.....prob sounds more like a bad IAC but u can figure it out.!

 

The first thing I would do is check for vacuum leaks.

Next, I would check the coolant level and that you don't have any air in your coolant system.

And finally, I would adjust the idle. It could be a tad bit too high.

Good luck! BTW, a bad TPS can give you the bouncing idle symptom, but so can these other things.

 

maybe a vac leak.

 

do you have a CEL? I would say IACV before TPS though

 

I agree either low coolant level or IAC, I've ran into both of those but never a bad TPS, not saying it can't happen though..

 

Thanks for the responses guys.

Just to Answer a couple of questions.

I have no CEL on right now.
We bled the coolant system and Added more afterwards. It is Definitely full.
I haven't tried unplugging the TPS sensor just cause I wasn't sure what plug it actually was until last night.

I'm gonna be tinkering around with it a bit. If I figure out the problem I will post it here. Until then keep the Suggestions comming.