VT INTERMITTANT IDLE DROP DOING MY HEAD IN

[poppy bill]

Hi all. I have a 2000 vt v6 that has a drop in revs while idling in drive approx 10 minutes after starting. revs drop down like it is missing and then comes back up again. Have taken it to two mechanics but cant find the problem. No codes are showing. Any ideas ?

 

[lout]

egr valve or iac solenoid?

 

[MR VXS2]

As above in previous post.

+Remove fuel filter and drain into clear container to inspect. Replace with new filter and if the old one was dirty, throw in some injection cleaner in next servo visit.

(i had a vr ute do this to me once, the fuel pump died about 3 weeks later. Id be sitting idling away at the lights, the revs would drop, then it would surge up and come back to idle again.)

 

[poppy bill]

Thanks MR VXS2 fuel pump was changed about 12 months ago. Filter looks ok but have added injector cleaner anyway. I took off the EGR valve like lout suggested and cleaned it out. Seems to be idling better and has not dropped revs yet. time will tell.

 

[MR VXS2]

All good, keep us posted.

 

[poppy bill]

have done all that was suggested and thought that was it but is still dropping revs at lights. mechanic is going to swap over the throttle body with one that is working. lets see how that goes.

 

[poppy bill]

changed throttle body but still dropping revs. found a code for the cam sensor and changed that and thought that was it because car ran fine for 3 days but **** it all it done it again. hahaha going nuts.

 

[lout]

try swapping dfi module with known good one

 

[SavVYute]

With the drop in revs happening about 10 minutes after starting it might be something related to the oxygen sensors activating as the car's computer goes from open to closed loop mode, trying to bring the fuel to air ratio back to where it should be.
Are all the engine's vacuum hoses connected tight? No leaks or cracks?

 

[devilly]

could be tps sensor failing.