strange idle problem

[Gtstu]

A friend of mines Gt has a strange idle problem basicly it idles wherever it wants to. tonite it was idling at 2k rpm but other times it can idle at 3.5k rpm. Iv checcked for leaks on all the vac pipes around the inlet etc and havnt found any leaks. If i unplug the idle controll valve nothing happens atall thinking it could be this any ideas?

 

[Gtstu]

any 1? had a search and found nothing really.

 

[leon]

i had that last night sort of, my glanza v was sittin at about 1.2/3k revs for abit, any ideas why anyone????

 

[danyor]

Im not sure is the turbo and the N/A engine ICV are the same. Sometimes valve can stick in one position. Simptoms idel high when you are stationary and idel up and down when you are on the move on neutral gear. Hope you understand me.

 

[Sigma]

Im not sure is the turbo and the N/A engine ICV are the same. Sometimes valve can stick in one position. Simptoms idel high when you are stationary and idel up and down when you are on the move on neutral gear. Hope you understand me.

Have this exact fault.

Dirty ICV?

 

[SupaStu]

Might be worth putting a new PCV valve on it, they are only about £25 from Toyota.

If that does not work, you could check the ICV valve on the inlet manifold, clean it first, or try a "good" working one. If this is working correctly it will regulate the idle, £100 from Toyota.

 

[Sigma]

I have the pipe from the PCV going to a catch tank, and the hole where the PCV pipes into the inlet manifold blocked off.

Would it be worth cleaning out the ICV on the inlet mani?

 

[SupaStu]

I have the pipe from the PCV going to a catch tank, and the hole where the PCV pipes into the inlet manifold blocked off.

Would it be worth cleaning out the ICV on the inlet mani?

Worth a try, my idle would go from 2k to down below 1k, then around 500, then stall occasionally. Changed the ICV and it was brand new, sorted.

 

[Sigma]

Cool! Ordered

 

[danyor]

To repair my one I removed it. But you can try this, knock on top of the valve when the car reach normal temperature and idle will drop. If not, you have to remove the valve there is the axle in middle which rotates between 2 magnets. When you remove it /check for rust or something/ usually it will unstick itself. You might have to adjust the idle slightly when you put everething together.
Note: dont try to force axel to make full revolution, it can only move slightly to the left or right

 

[Gtstu]

Would a faulty coolant temp sensor cuase high idle?

 

[Gtstu]

still having issues iv changed the idle controll valve still idles at 2k. iv checked for vac leaks etc and found none.starting to think coolat temp senor or throttle position valve? but shouldnt this bring the eml on? any input would be great.

 

[Texx]

For engine speed to increase the amount of air entering the engine needs to be increased. Making adjustments to the air/fuel mixture and ignition timing can have a small affect on engine speed, but not the amount you are experiencing. I would block off all ports on the intake manifold between the throttle body and cylinder head to determine if any are causing an air leak. The IAC valve can be left bolted to the manifold, just block off or crimp the hose so it cannot draw in any air.

If this doesn't appear to make any difference then the high idle could be caused by a leaking intake manifold gasket or fuel injector seal.

 

[Gtstu]

ill try that i think i might pull the intake of and see what the gasket is like . could head gasket be the problem? and i didnt think about checking the injector seals thanks Texx ill give that a go.

 

[Texx]

Rather than pulling the manifold off or injectors out, try gradually and lightly spraying some WD40 around these areas and see if the engine revs drop.

 

[Gtstu]

ok mate will do thank you.

 

[Gtstu]

well i sprayed brake cleaner all over the inlet and pipes and found nothing i have blocked to pcv clamped the pipes off i can get to and it still idles at 2krpm .would coolant temp sensor or tps increase the idle that much but bring no light on?iv changed the idle control valve also.really stumped on this one now. mite remove the inlet and see if the gasket has failed.any ideas??