TPS Question
TPS Question
When I unplug my TPS while the car is running, the idle goes up higher, is this normal? And When I try to adjust my idle with the TPS off.. I can't seem to get it to idle at 650rpms or 750 by adjusting the screw.. when I turn the screw all the way to the right.. the idle is about 1.5k... I start turning to the left and the idle raises up more. It's like it wont go lower thank 1.5k with the tps off.. when I plug the tps back in...I can adjust it however. Is there somthing wrong?
Re: TPS Question (tiger)
It could be one of a few things, but more than likely, your iacv is fouled up from carbon - basically, it's so gunked up that you can't lower idle anymore (stuck sort of full open). This is a common problem on our cars... I had the same problem .
Anyway, the usual way to fix it is to remove the unit, clean the crap out of it w/ carb cleaner - some ppl on this forum have even gone so far as to let the unit soak in carb cleaner overnight. Get a new gasket (or rtv sealant) hook it back up and see if you still have the same problem.
Another thing you may want to check is for vacuum leaks, which will affect the idle also, and loose/corroded connectors on the wiring harness - I found my engine temp sensor on the intake manifold near the bleeder valve had a faulty connector/harness (someone f'ed w/ it before I had the car) and would fluctuate idle when you wiggle the harness. The sensor itself, a long w/ a couple others on the intake manifold were a little gunked up.
Lastly, also make sure your tps is set correctly. On my car (ka24e), i had to reset the tps so that it reads <.5volts closed, which it wasn't. Should be around 4.5volts open. Not sure what engine you got, but that was the fsm specs for mine.
I cleaned all those up, and "so far" everything seems better. I had a few other problems I've been fixing on the car, so I haven't had a chance to fix my timing again yet.
Anyway, the usual way to fix it is to remove the unit, clean the crap out of it w/ carb cleaner - some ppl on this forum have even gone so far as to let the unit soak in carb cleaner overnight. Get a new gasket (or rtv sealant) hook it back up and see if you still have the same problem.
Another thing you may want to check is for vacuum leaks, which will affect the idle also, and loose/corroded connectors on the wiring harness - I found my engine temp sensor on the intake manifold near the bleeder valve had a faulty connector/harness (someone f'ed w/ it before I had the car) and would fluctuate idle when you wiggle the harness. The sensor itself, a long w/ a couple others on the intake manifold were a little gunked up.
Lastly, also make sure your tps is set correctly. On my car (ka24e), i had to reset the tps so that it reads <.5volts closed, which it wasn't. Should be around 4.5volts open. Not sure what engine you got, but that was the fsm specs for mine.
I cleaned all those up, and "so far" everything seems better. I had a few other problems I've been fixing on the car, so I haven't had a chance to fix my timing again yet.
Re: TPS Question (brokeAs240sx)
ok, thanks for your replies. I'm pretty sure my iacv is clean.. but maybe one day i'll take it off and clean it good. I can get to it pretty easy now that my egr crap is out of the way. I replaced the harness and the coolant temp sensor when i first got the car.. (9 months ago) I would bet that my iacv is the prob since I can't make it idle low with the tps off..