Maf?

[shocar]

Ok, 92 mtx is running rich as I smell a bit of gasoline going down the highway with the AC on. I left a light on and the battery went completely dead after I noticed this ( not sure if this has anything to do with it ) . I clean the air filter ( K&N) start the car up and it runs rough. Checked for vacuum leak and nothing found. Unplug the MAF and the car runs a lot better. Took it apart and it not dirty. No check engine lights. What do you think is going on here? One wierd thing I notice went today when I went to move the car after I jumped the car to get it starte. When I let the hood fall to close it, the car stumbled like it was going to dye. Weird, any ideas? Could it just be bad connection at the MAF?

 

[Slo-Sho]

One possibility is that you put too much oil on the K&N and the excess coated the two fragile heating elements inside the MAF...maybe...

 

[93rev2sev]

MAF sensor: You can't tell if it's fouled by looking at it(in lots of cases). If it IS dirty, the extra fuel you are burning will more than pay for a can of MAF cleaner.

 

[hawkeye18]

If the car runs better when you unplug the MAF, then the MAF is most certainly the culprit. Clean it.

 

[Kens1992mtxSHO]

Clean the MAF. You also may want to check your purge canister as this can also cause the smell of gasoline with the A/C on in the car and around the engine bay.

 

[shocar]

where exactly is the purge canister on the mtx?

 

[luigisho]

It's not the problem. If the car runs better with the MAF unplugged then that's the problem.

 

[hawkeye18]

Seriously, it's one screw to get to the MAF. Undo the two latches that let you get to the air filter. See that hose clamp on the side of the MAF connector closer to the throttle body? Loosen that up, and wiggle the whole airbox lid assembly out of that hose. Look at the MAF; you'll see a mesh screen. You can either get it off (there's a snap ring) or spray from the back. Spray the sample tube liberally with either Q-D MAF cleaner or Q-D Electronics cleaner. DO NOT use anything else (carb cleaner, engine cleaner, etc); doing so will damage the *very* sensitive wires in the MAF.

 

[shocar]

Have the maf cleaner, will get back to you as to the result.

 

[luigisho]

Cleaning the filament usually does the trick. Keep in mind that if it continues to run better with the MAF unplugged, after it's been cleaned, then the unit is bad and you need another one. Don't get distracted with the other info in the thread. The key is that it runs poorly and greatly improves when the MAF is unplugged. That's the malfunctioning part.