02 GMC Sierra MFS

[fishingstar]

I have checked the codes on my pickup and it has 3 codes.

mass flow senor, lean bank 1 lean bank 2.

has anybody had any luck with cleaning the senor or should that just get replaced? Does the other codes have any thing to do with the msf?

how can I clear the light after this is done? The light came on when we got that heavy wet snow in early winter and went out the next day.

Any information would be great

Thanks

Dan

[JOHNBIGDOG]

Engine size and actual mileage would be nice along with the actual MAF code.

On a side not you can try cleaning the MAF sensor with MAF sensor cleaner by crc then disconnecting the battery for say a half hour, drive it and see what happens. The MAF may be causing the lean codes.

[Jeremy airjer W]

If it went out the next day and has not come back on since I wouldn't worry about it.

[fishingstar]

The truck has a 5.3 and has 125,000 on it.

On sat. it came back on after driving on a wet highway.

it went on and off in the heavy wet snow in December.

I was hoping the lean codes were from the dirty mfs

[Jeremy airjer W]

What does the air filter look like?

I'm guessing you never checked or cleared the codes when this happened last month? So you don't know if these ar the same codes, new codes, or a combination of old and new codes?

As suggest try cleaning the MAF with MAF sensor cleaner, available at any parts store. Clear the codes with a code reader, you can't get one for about $50. Or swing by autozone and see if they will do this for you.

If the lean codes come back but not the MAF code than I would bet the intake plenum gaskets are leaking. If all three come back than possibly the MAF sensor has failed.

[fishingstar]

ok I will try cleaning it. any why to clear codes whit out a code reader.

I don't have one and the part stores don't do it out here.

Dan

[Scott K]

Another option I use is rubbing alcohol and a qtip. Just lightly rub the wet qtip on the heating element.

[fishingstar]

So I cleaned the senor last night and today on thr way to work light went out. Now what should be done with the codes that are in the computer or should I just leave it.

thanks for your help

Dan

[Jeremy airjer W]

even though the light is off the codes are still stored in memory. It would be best to clear them. If the light should come back on and they are not cleared than the old codes will be in history and may lead to some confusion if the new codes are different or only some of the old codes return.

Every once and a while we will see a vehicle in for driveability problems and when codes are checked there are two pages worth. Its easier to clear them all and see what comes back rather than worry about or persue all of them.