Idle Problem Questions: Yep, i used the search

[Bimmerboy91]

so i used the search but i couldnt quite get the answers i was looking for. and ill add some more questions as we go, so here we go

what exactly does the TPS do? where is the TPS located? How can the TPS be cleaned? How can the TPS be adjusted? would the TPS cause low idle or hunting idle? What about light to medium misfires at idle

Id appreciate the input

thanks

[jlevie]

The TPS is located under the throttle body on an M20B25 engine. It contains two switches, one that closes at idle and one that closes at wide open throttle. You really can't clean a TPS, so if one of the switches is not working a replacement will be necessary. The adjustment procedure is in the Bentley manual.

A bad or misadjusted TPS will affect idle, but an intake leak or sticky/bad ICV is just as likely to be the cause.

[Bimmerboy91]

would a bad or worn Distributor cap and rotor cause hard starts (cold or warm) and misfires?

[Turf1600]

Spray carb cleaner around all of your intake gaskets. If you experience a change in idle when spraying - there's a leak present. Otherwise - I suspect a bad IAC.

[Turf1600]

would a bad or worn Distributor cap and rotor cause hard starts (cold or warm) and misfires?

If they are bad or worn - replace them anyways.

[Bimmerboy91]

what is the IAC?

could i spray electrical parts cleaner?

but would a worn distributor cap and rotor cause hard starts and cause some misfires? (ones that shake the car a little at idle)

thanks

[Turf1600]

what is the IAC?

could i spray electrical parts cleaner?

but would a worn distributor cap and rotor cause hard starts and cause some misfires? (ones that shake the car a little at idle)

thanks

no - use something that will burn easily. It depends on the amount of wear on your tune up parts. Just do a tune up and see how it goes.

[redhatpat]

what is the IAC?

could i spray electrical parts cleaner?

If he means the idle control valve (ICV), then you can spray it clean with some throttle body cleaner.

but would a worn distributor cap and rotor cause hard starts and cause some misfires? (ones that shake the car a little at idle)

thanks

Absolutely. They're cheap(ish) and easy to change out. If in any doubt about their condition, change them. Also test the coil for its condition. It's another thing that can cause poor starts and misfires and is easy to replace.

[Bimmerboy91]

check out my distributor:





comments?

[netcsk]

Your pictures aren't good enough to tell, but it appears to look ok.

You're looking for corrosion or badly worn spots on any of the metal contacts both on the cap and rotor. But really, they aren't bad to replace anyway.

[Bimmerboy91]

yeah i took those pics quick but whats up with all the dust in there? and the cap terminals feel eroded when you run your finger on the terminals you can feel that they are rough and you can see that the terminals look a little charred or black. the rotor tip looks burnt.

i really need to look into a big tune up of key parts. today it almost didnt start when i went to the store.

thanks for the input guys