MAP Sensor
Thread Starter
Pro
Joined: Apr 2006
Posts: 607
Likes: 1
From: Chesterfield Virginia
MAP Sensor
I just washed my car again and I get again hesitation, car stalling out, rough idle. The code it throws is P1639 - 5 volt reference 2 circuit and P0107 Map sensor circuit low voltage. The battery is at 13 volts. Could I have a bad MAP sensor. But it only happened the last two times I washed my car. Ran fine otherwise.
Instructor
Joined: Aug 2005
Posts: 133
Likes: 0
From: OKC OK
I don't think its your MAP sensor. I think you are probably shorting out a circuit after the wash and your codes are a symptom of that.
Before any forum old-timers jump all over me for giving any advice at all, I would like to state the following: I'm not a GM engineer (or any other kind for that matter), a forum hero wanna-be, nor do I profess to know anything about cars; excpet that I do like them and I do a fair bit of wrenching on my own etc.
Having said that, maybe you ought to inspect the ground points on the car. Assuming you are also washing the motor, do you cover the alternator? Does it return to normal after a few days of drying out? What is your wash method? What year is your car? More info is better...
R/
Dustin
Before any forum old-timers jump all over me for giving any advice at all, I would like to state the following: I'm not a GM engineer (or any other kind for that matter), a forum hero wanna-be, nor do I profess to know anything about cars; excpet that I do like them and I do a fair bit of wrenching on my own etc.
Having said that, maybe you ought to inspect the ground points on the car. Assuming you are also washing the motor, do you cover the alternator? Does it return to normal after a few days of drying out? What is your wash method? What year is your car? More info is better...
R/
Dustin
Thread Starter
Pro
Joined: Apr 2006
Posts: 607
Likes: 1
From: Chesterfield Virginia
Thanks for the response. I actually don't wash the engine, the car is just washed on the outside. It's a 98 coupe. I washed it about 10 times after i got it with no problems. The last two times the same issue. I disconnect the negative wire from the battery for several hours and then the thing is running fine. I see no water in the battery area so maybe i am hitting a ground point. Guess i'll just have to be careful next time or wash a quarter of the car at a time to see if i can pinpoint the area and go from there.
