Expert: Roland Finston - 10/14/2011

Question
QUESTION: Hi, I have a 2008 Chrysler Sebring, V6, 2.7L engine that occasionally wants to stall and then the RPM's ramp up and the car wants to surge forward. This usually happens sitting at a stop light. Sometimes the car will stall after this happens. This is an intermittent problem that I need to get fixed.
Thank You for your time.

ANSWER: Hi Larry,
There is likely a fault that has been sensed by the engine controller and given a code number. The code reader needs to be plugged into a socket under the dash to the left of the steering column. Nationwide autoparts stores will often do a free code readout, such as Autozone. So ask at such a store, and ask for the specific code numbers, what they mean, and what they recommend to do. Then write back and let me know and we'll check that against the manual and decide how to correct it. An independent garage will usually do a readout for $40 if you can't find it for free. This is the most efficient/accurate way to resolve something like this.
Roland

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QUESTION: I checked for any codes with a Black and Decker smart scan code reader, OBD 2 3.0. The scanner read "NO CODES".What should I try next. Once again Thank You for your advice.

Answer
Hi Larry,
The most likely item would be the exhaust gas recirculation valve not closing off tightly when you come to a stop which then allows exhaust gas into the intake manifold which leans out the mixture and causes it to stumble. The valve is only supposed to be open when you are cruising alond at a constant speed.  My only question would be is there an egr valve on your '08 2.7L engine? My latest manual is for '06 and it does show there to be 2.7L egr valve.
Take a look on the underhood sticker that will show all the components of the emission control system to see if an egr valve is indicated. If so I would remove and clean and lubricate the valve stem if accessible and also check for a build up of crud at the valve head inside the pipe.
If there is no egr valve then I believe the only way to get a handle on this is via a diagnostic tool that shows the operating parameters of all the ignition/fuel system/sensors to see if there is one that appears to be marginal and yet not so bad as to set a fault code. This can often happen but it takes access to the tool and skill/familiarity with its interpretation.
Of course if you can't induce it to show its bad behavior there is often no point in going to a shop. Once it is frequesnt/predictable then the chances improve for diagnosis/repair.
Roland