mass air flow sensor

[richards72chevy]

My 01 blazer is running bad again.The rpm fluctuates and then I can press the pedal to the floor and nothing happens.First my scanner said no link.Tried it again it said 4 codes.It gave me the code p0101 twice then p0756 twice.p0101 is a trans shift solenoid and the p0756 is maf sensor.I guess the maf can trip the solenoids.I know on some other vehicles the maf can be disconnected or bypassed.Can I do this on my blazer?Can the maf be tested at the parts store?I also noticed they sell a spray that claims to clean the maf.Does this work?Thanks.

[76C10Stepside]

Have you tried clearing the codes and checking them again? Sometimes old codes are still in there from a previous situation. If you still get the two codes, I'd focus on the FIRST code reported and whatever part (or parts) are indicated. I once had a bad MAF sensor on a Buick 3.8 and got two different codes. The first code was for the MAF, forget what the other one was (probably O2 sensor). I tried cleaning the MAF first, with no improvement, so bought a new one and that cured the problem and BOTH trouble codes went away. Not saying your MAF might not just need cleaning. If you drive on dry dirt roads or through a lot of mud/rivers or something, it might be really grungy.

[richards72chevy]

Replaced the maf.Must be the shift solenoids.

[76C10Stepside]

Richard, did you ever check for trouble codes? Check for dirty harness plug/connections.

[richards72chevy]

Cleared the codes.Runs like crap.Im getting the code p0300 now which is multiple misfire.

[76C10Stepside]

Originally Posted by richards72chevy

Cleared the codes.Runs like crap.Im getting the code p0300 now which is multiple misfire.

That does not sound like mass airflow sensor. The MAF just feeds atmospheric data to the ECM to tell it when and how much to adjust the air/fuel ratio. With a dead MAF, the engine will idle fast and run crappy, but should not actually misfire.

Have you pulled the harness plug(s) and checked for corrosion? I'd do that next, as it's very easy to do.

Pull the spark plugs and check them for fouling, etc.

Check for arcing from the plugs and wires. Arcing can be caused by cracked plug insulator, plug boot pulled up too high and bad/broken ignition wires.

Make sure none of your ignition wires run parallel and touch each other (causes "crossfire").

[richards72chevy]

Removed one spark plug today and it is extremely black on one side and brown on the other side.Another weird thing I noticed was my exhaust getting really hot in a short period of time.Less than a minute.I coulnt touch the front of my catylatic converter but the back of it was just luke warm.Do these become clogged over time?

[76C10Stepside]

Originally Posted by richards72chevy

Removed one spark plug today and it is extremely black on one side and brown on the other side.Another weird thing I noticed was my exhaust getting really hot in a short period of time.Less than a minute.I coulnt touch the front of my catylatic converter but the back of it was just luke warm.Do these become clogged over time?

Brownish or tan color with little or no visible wear on electrode is "normal". Black is not normal. Pull ALL the plugs and check each one against this chart. Clean and gap each plug or replace them if old:



How long since the last tune-up (oil/filter, plugs)?

As for the catalytic converter, they do get hot (that's how they cook the unburnt gases), but it usually takes awhile for them to heat up, and I'm pretty sure they should not be hot at the front and cold at the back. Yours may be cooked. They do have to be replaced eventually. Bad O2 sensors and other problems can also shorten the life of the catalytic converter. Code P0040 indicates bad O2 sensor.

Is your Check Engine/Service Engine Soon light going on?

The OBDII codes are here.