Expert: Roland Finston - 11/14/2011

Question
QUESTION: I have a rough idle condition that is intermittent and seems to only happen shortly after starting the vehicle.  Sebring '04 Sedan 2.4 DOHC with 89500 miles.

New timing belt, battery, camshaft sensor at 83000.  Spark plugs and wires were replaced at around 86000 miles.  I know this is a BROAD problem, but just wondering where I should start.. Intermittent P0440 and P0441 codes.  Saw an O2 sensor code once about two-three years ago, but never again.  Gas mileage is so-so.

Was thinking of starting at the EGR valve and dumping in some fuel system cleaner... Advice?

ANSWER: Hi Chris,
If the egr has an exposed valve stem (between the body of the valve and the round actuator, then it should have a slot into which you can insert the tip of a screwdriver and move the stem back and forth. See if it closes to a dead stop via the internal spring action and moves easily. If not then spray some WD-40 on the stem where it enters the valve body and then move the stem some more to free it up. Otherwise, remove and clean the valve would be worth trying.
On the 0440 and 0441 codes those have to do with the evap/purge solenoid which is part of the fuel vapor recovery system. It is located in the engine compartment beneath the master brake unit and it too has a round vacuum top and a wire connector. Check all the vacuum hoses involved with it and also the balance of that system of hoses. There is a method for checking the function of the solenoid which is too long to type in. But I can attach a copy from the CD that I have of the code manual to an email which I send to you directly. To do that I need to have your email address. And the only way to tell me it is to ask a NEW question, tell me the address in the text area, and then click on the make question PRIVATE option. If you don't follow this instruction exactly your address will be erased automatically.
Roland

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QUESTION: Roland

Thank you for quick response.  Unless you tell me P0440 and P0441 could be related, I will hold of on this.  I have already done all I can without getting underneath the car, including replacing the purge solenoid.

However, could you tell me where the EGR valve is and what it looks like?

Answer
The egr is mounted horizontally on the head of the engine, at the rear of the head close to the corner which is nearer to the firewall. If those fault codes keep re-appearing after being erased, then it is possible that a vacuum leak in one of the several hoses will cause a rough idle.