Pontiac Repair: Map Sensor, throttle position sensor, mass air flow sensor

Question
QUESTION: I had the map sensor replaced on my 2005 Pontiac Grand Am (V6), now my car is idling at around 2 rpm's and accelerating even when I let off the gas.  Is this normal or does it need adjusting?

ANSWER: Hi Lacey:

No the MAP sensor doesn't need any adjustment. Why was it replaced, for this issue? My guess it one of two things either the engine has a vacuum leak or there is an issue with the throttle position sensor where the volatge is to high at idle or the engine computer sees a % of throttle input evne know you do not have your foot of the gas.you will need an engine scan to see if this is the catual issue or not. one other possibility is the throttle body is binding or the gas pedal or linkage is binding and keeping the throttle open a bit. Hope that helps you out. good luck :}


---------- FOLLOW-UP ----------

QUESTION: My car recently had water damage.  I drove into some water that was deeper than I thought.  The water was sucked up through the tail pipe, the car died and wouldn't crank again.  The dealership mechanic changed the oil, spark plugs and fuel filter.  Then decided the only problem was the MAP sensor so it was replaced also.  Now I have the acceleration problem.  Is it possible the water has affected other electronic components?

Answer
Yes it is possible and water doesn't get sucked up the tail pipe It filled it up once the car died the exhaust gases from the engine stop it from comming in that way untill the engine quit running. The water must have gotten sucke into the engine through the air filter/air cleaner. There is a VERY important sensor in the intake system it's called a mass air flow sensor If that got real wet then that would be the sesnor I would look at more so that an other one. That is a main input to the engine to let it know how much air the engine is using and how much of a load is on the engine. I would still look at the throttle position sensor as well. Take it back to the dealer and let them look at it. Ask that a driveability technician look at it. He will know exactly what to be looking for. Let them know the histor behind this as well if you choose to goto a different dealer. Good luck :)