05 CTT. Please help me solve this.
When I come to a complete stop at stop lights or stop signs I notice my RPM drop to one bar from normal idle position and then goes back up to normal idle position again. The engine vibrate a little when the RPM drop to one bar. After that everything is normal again. No lose of power and now after a couple months I get CEL. I do still get the RPM drop problem. Can it be something with the Air Seperator systems?

Anyone know what causes this? Any comments is appreciated.

Many thanks

 

Not sure about the idle drop, but I've heard/read that the vibration when coming to a stop is due to engine mounts needing replacement.

 

Is this a DIY work? I have done what the other Rennlists fella/gals suggests and still the same result.

 

Take a look at this thread here. Some people describing a similar issue to what you're stating so it may or may not be helpful. Is there a CEL on?

 

Thank you for the link. No CEL on. I never would of thought the fuel pump is also a possibility. Although, the fuel pump has not been change since 2005. I will look into it. Thank you.

 

Well, the CEL just came on today. Now it's really making me worry.

 

Did you pull the code?

 

Not yet. Will take it to the dealer for them check the code (free). Will let you know the status.

 

Let me know what you find.

 

Ok. This is what the dealer found.

0968 = Right direction indicator light
0532 = Power supply
0908 = Wiper motor (with control module)

None of those codes don't relate to my symptoms. Is it still the motor mount?

 

Ok, so check for vacuum leaks by doing a smoke test. Then, check the crank case vacuum as it should be around 7 inches of water at idle with all loads off. If it's higher, then the crank case vent valve is probably faulty. Other than that, check the basic maintenance items. How many miles are on the car?

 

Ok I will check on those. 131k miles. Again thank you for your time. I'll keep you posted.

 

The idle wouldn't dip if it's the motor mount. Knowing that it has that mileage, I'd lean towards the crank case vacuum issue. It could also be the cam timing at that mileage. You'll need to remove the valve covers and check the timing if everything else that I suggested checks out. Keep me posted and I'll try and help out as best as I can.