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        General >> Problems >> Throttle position sensor
        
(Message started by: cossieguy on Dec 6^th, 2006, 3:42pm)

Title: Throttle position sensor
Post by cossieguy on Dec 6^th, 2006, 3:42pm

Right i'm almost 100% certain i've got a problem to do with the TPS. After booting the car (Using kickdown) the idle and driving revs are too high 1000-1100 rpm at idle. If I reset the car(Battery off) it idles fine until the next time i boot it etc. How do i check the TPS? I haven't got access to obd scan, is that the only way to check this out? Has anyone else got/had a similar fault with the tps? It seems that by using kickdown(WOT) it throws the TPS off somehow, is that possible?
Guy.

Title: Re: Throttle position sensor
Post by scorpio_man on Dec 6^th, 2006, 3:59pm

hi there

you can check it with a meter set to 5 volts. can't remember if it goes up or down. should be a nice smooth action, though.

hth

Title: Re: Throttle position sensor
Post by harry.m1byt on Dec 6^th, 2006, 4:15pm

Getting back to basics - So far as I am aware it is a simple potentiometer, just like a volume control on a radio. Three terminals - one for each end of the pot' and the third the sliding variable resistance contact.

So between the first two should be a steady fixed resistance - resistance measured between either of these two and the third one should be adjustable by turning the shaft. If the pot is sound and clean, then the actual value should change nice and smoothly as you turn the shaft.

Some one may be able to advise actual values against which you could compare your TPS.

In use - two different stable voltages are applied one to each end of the pot, then the third pin outputs a voltage dependant upon the position of the throttle.

Title: Re: Throttle position sensor
Post by cossieguy on Dec 6^th, 2006, 9:17pm

Further development, as mentioned in other threads i've now fitted my in line crankcase breather filter and thoroughly cleaned my viper induction kit. Took car out and gave it a gentle reminder it's a cossie ;) stopped car several times and put in park/neutral and couldn't get the problem to show itself :) Bit early to say its gone but looking promising.
Guy.

Title: Re: Throttle position sensor
Post by Octavian_P on Dec 7^th, 2006, 9:28am

From what you say maybe the throttle plates stick. When you kick it down the plates move more and maybe the have gung deposits on them and don't revert to neutral position right away. So it could be coincidence when you take the battery out, or the ECU ajuts it's self for the slight open throttle body.

Well it ore of a hunche but worth checking.

Cheers

Title: Re: Throttle position sensor
Post by cossieguy on Dec 7^th, 2006, 9:55am

How do i check/clean the throttle plates? Wouldn't even know where to start looking.
Guy.

Title: Re: Throttle position sensor
Post by scorpio_man on Dec 7^th, 2006, 1:38pm

hi there

this (http://www.btinternet.com/~madmole/HowDoI/Howdoi.html) is for a mondeo, but give you a good idea of what to do.

on the 24v, i think you need to take off the inlet mainifolds first.

hth