Map sensor

[twt]

I have forgot what the MAP sensor is & what it does. Is there a mod to fool the computer?? My truck bypasses boost when changing gears, am I headed the right direction?? T.Tolle

 

[DaveBen]

The MAP sensor is Manifold Air Pressure sensor. It tells the PCM the absolute pressure of the manifold under all operating areas.

Dave

 

[BIG JOE]

See the "What is this" Post ?

 

[RON.B54]

Could a bad map sensor cause a low boost or no boost at all fault ?

 

[BIG JOE]

Could a bad map sensor cause a low boost or no boost at all fault ?

It could, but tell us more ?

 

[RON.B54]

I have a code P1247 and P1248. The truck appears to run ok but now and then it tends to feel heavy, alittle slow to accelerate unless you give it move fuel

 

[BIG JOE]

I have a code P1247 and P1248. The truck appears to run ok but now and then it tends to feel heavy, alittle slow to accelerate unless you give it move fuel

Okay, thats Low Boost and Boost not detected.

You say.. but now and then it tends to feel heavy ?

That could be: A loose or leaking I/C boot, dirty air filter, dirty fuel filter or you've over boosted the PCM pre-set limits (MAP sensor controlled) for boost.. and the PCM has set the 1247/1248 codes and gone to the de-fuel mode. (cuts fuel= power)

If yer Scanner has the ability to erase to codes (?) do that. If not, disconnect yer batteries (both) for 20 minutes.... see if that helps... Let us know ?

Joe

 

[RON.B54]

Thank you Big Joe I'll give it a try and let you know what happens