Map Sensor

noahraysanders · June 25, 2009

What would a bad Map sensor cause my engine to do? I have a 2002 silverado 5.3 liter

bigbengalbubba · June 25, 2009

What would a bad Map sensor cause my engine to do? I have a 2002 silverado 5.3 liter

It would cause your NAV unit to take you to incorrect destinations. (Sorry couldn't resist)

I think you mean MAF sensor. And when mine needed cleaning it caused an occasional stutter in the engine like a misfire. Cleaned it and it's been fine ever since. There may be other symptoms as well.

Draenor · June 25, 2009

The engine would run rough. It would also run poor under a load, since the ECM cannot see the vacuum it will not advance(or retard) timing.

brims · June 25, 2009

What would a bad Map sensor cause my engine to do? I have a 2002 silverado 5.3 liter

It would cause your NAV unit to take you to incorrect destinations. (Sorry couldn't resist)

I think you mean MAF sensor. And when mine needed cleaning it caused an occasional stutter in the engine like a misfire. Cleaned it and it's been fine ever since. There may be other symptoms as well.

There's a MAP (manifold air pressure) and a MAF (mass air flow) sensor. I'm not sure what a bad MAP sensor would do, but it sounds like John answered that.

bigbengalbubba · June 25, 2009

What would a bad Map sensor cause my engine to do? I have a 2002 silverado 5.3 liter

It would cause your NAV unit to take you to incorrect destinations. (Sorry couldn't resist)

I think you mean MAF sensor. And when mine needed cleaning it caused an occasional stutter in the engine like a misfire. Cleaned it and it's been fine ever since. There may be other symptoms as well.

There's a MAP (manifold air pressure) and a MAF (mass air flow) sensor. I'm not sure what a bad MAP sensor would do, but it sounds like John answered that.

My apologies. It just jumped out at me and I went with it.

brims · June 26, 2009

What would a bad Map sensor cause my engine to do? I have a 2002 silverado 5.3 liter

It would cause your NAV unit to take you to incorrect destinations. (Sorry couldn't resist)

I think you mean MAF sensor. And when mine needed cleaning it caused an occasional stutter in the engine like a misfire. Cleaned it and it's been fine ever since. There may be other symptoms as well.

There's a MAP (manifold air pressure) and a MAF (mass air flow) sensor. I'm not sure what a bad MAP sensor would do, but it sounds like John answered that.

My apologies. It just jumped out at me and I went with it.

Just trying to help out.

noahraysanders · June 26, 2009

What would a bad Map sensor cause my engine to do? I have a 2002 silverado 5.3 liter

It would cause your NAV unit to take you to incorrect destinations. (Sorry couldn't resist)

I think you mean MAF sensor. And when mine needed cleaning it caused an occasional stutter in the engine like a misfire. Cleaned it and it's been fine ever since. There may be other symptoms as well.

There's a MAP (manifold air pressure) and a MAF (mass air flow) sensor. I'm not sure what a bad MAP sensor would do, but it sounds like John answered that.

My apologies. It just jumped out at me and I went with it.

Just trying to help out.

its just that my rpms surge when im driving 40-50 mph and someone told me it could be my map sensor. i just replaced my knock sensors and while i was in there i cleaned my map sensor with brake fluid to see if that would help but engine is still surging.. no one on this site has been able to figure it out.

brims · June 26, 2009

I don't think brake fluid is the right thing to use on the MAP sensor, or MAF for that matter. It may be toast.

2500sierra · June 27, 2009

The MAP sensor may have something to do with you surging and what you might think is a tcc lockup issue. I am not sure but i know on my older truck (TH 350C tranny) it used a vacuum diaphragm switch to disengage lockup under heavy loads. Sounds like the MAP sensor is replacing that old style switch.

Draenor · June 27, 2009

I don't think brake fluid is the right thing to use on the MAP sensor, or MAF for that matter. It may be toast.

+1 That was not a good idea to use the brake fluid.

The MAP sensor may have something to do with you surging and what you might think is a tcc lockup issue. I am not sure but i know on my older truck (TH 350C tranny) it used a vacuum diaphragm switch to disengage lockup under heavy loads. Sounds like the MAP sensor is replacing that old style switch.

+1 It sounds like the TCC is not locking up correctly.

The torque converter clutch solenoid is going out. It is in the valve body and can easily be replaced.

Are you getting ant DTCs?

alwcurlz · June 27, 2009

I don't think brake fluid is the right thing to use on the MAP sensor, or MAF for that matter. It may be toast.

+1 That was not a good idea to use the brake fluid.

The MAP sensor may have something to do with you surging and what you might think is a tcc lockup issue. I am not sure but i know on my older truck (TH 350C tranny) it used a vacuum diaphragm switch to disengage lockup under heavy loads. Sounds like the MAP sensor is replacing that old style switch.

+1 It sounds like the TCC is not locking up correctly.

The torque converter clutch solenoid is going out. It is in the valve body and can easily be replaced.

Are you getting ant DTCs?

I think he may have meant "brake cleaner" maybe? I've used brake cleaner spray on things that would have needed carb cleaner spray since they do the same thing and work just as well.

brims · June 27, 2009

They sell MAF cleaner, which I would venture to say is the right thing to use. Could be a bunch of bull, but could be true.

noahraysanders · June 27, 2009

I don't think brake fluid is the right thing to use on the MAP sensor, or MAF for that matter. It may be toast.

+1 That was not a good idea to use the brake fluid.

The MAP sensor may have something to do with you surging and what you might think is a tcc lockup issue. I am not sure but i know on my older truck (TH 350C tranny) it used a vacuum diaphragm switch to disengage lockup under heavy loads. Sounds like the MAP sensor is replacing that old style switch.

+1 It sounds like the TCC is not locking up correctly.

The torque converter clutch solenoid is going out. It is in the valve body and can easily be replaced.

Are you getting ant DTCs?

whats a dtc?

2500sierra · June 28, 2009

Diagnostic Trouble Code AKA is your service engine soon light on?

Spurshot · June 30, 2009

Just to add to the confusion, I believe that the MAP has a feedback to the ECM/TCM for control of timing and fuel flow as well as shift points and torque converter lockup.

Chuck