FAQ: Mass Air Flow (MAF) Sensor Issues?

Does it change the way it runs if you unplug the MAF sensor?

Just tried that... There doesn't seem to be any differance at all- That means that the sensor is bad-Huh?

Yep.

What's a new sensor run?  I have a spare 98 TB with the maf sensor, might be willing to sell it.

Wow, a couple hundred at NAPA. Chris, I'll sell my spare TB with the sensor for $50 including shipping. I'll even pull the sensor and clean it properly before shipping.

That sounds good man... Many thanks

Replied to your PM.

will i tear anything up if i still drive it(but baby it) for a week till i can get another???

It should work. If you had a tuner it's a perfect opportunity to get some quality VE tuning done, since that requires the MAF unplugged anyway!!

I'd think you'd be safe to baby if for a while.

deekster_caddy wrote:

It should work. If you had a tuner it's a perfect opportunity to get some quality VE tuning done, since that requires the MAF unplugged anyway!!

Im still fresh out fo the starting gate as far as tuning goes. I have no idea what VE tuning is.(or BIN or some other stuff) But Im gunna keep on searchin and find out and if that fails I'll just ask about what i cant find w searching

Ok guys, refresh my memory... isn't there supposed to be a gasket or o-ring in the groove in the bottom side of the MAF sensor? Don't recall from last time I cleaned mine. The spare TB I pulled this sensor off of, had been cleaned up and spray painted, and there's no gasket on it. I'm pretty sure it should have one, and have told Chris to save his original gasket.

I don't recall seeing a gasket under mine when I had it out for cleaning last summer...

Well, there is what appears to be an O-ring groove around the perimeter of the mating surface of the sensor body. I can't imagine it serves any other purpose besides holding an O-ring. I "think" mine has one, just don't recall for sure. Considering you can't torque down much on the screws, I'd think an O-ring would be needed. Or at least a thin layer of RTV.

Got my maf in and it runs bette.
Should I wait a couple days before I go WOT, so i can give it time to get correct ltft's???

Was there a gasket or O-ring involved?

curious riv wrote:

Got my maf in and it runs bette.
Should I wait a couple days before I go WOT, so i can give it time to get correct ltft's???

Fuel trims really don't affect WOT. You should be fine. It takes about 30 minutes of driving to develop basic fuel trim info.

The one that I got from Dave had a o-ring on the round part that goes into the TB. (So does my old one) The was no gasket in the flat metal part that has the groove in it that looks like one should be there.

deekster_caddy wrote:

curious riv wrote:

Got my maf in and it runs bette.
Should I wait a couple days before I go WOT, so i can give it time to get correct ltft's???

Fuel trims really don't affect WOT.  You should be fine.  It takes about 30 minutes of driving to develop basic fuel trim info.

Thanks!!!

scanned(code reader) my car yesterday and the p0102 code is still there. I was under the impression that a MAF code will clear itself when the problem is fixed. Im going to check for vacuum leaks, cheack the connections, clean the IAC and TPS when I get home today. Does anyone have any other clues to why it still is showing a 'mass air flow circuit low voltage' code???

Can you erase the code with your reader? I'd do that and then let it run the tests again, if the code comes back then I would look into other things.

thanks Andrew,
I read that any code for the MAF is a category 'A'-meaning that as soon as the problem is fixed the code will clear itself... I'll clear it first chance i get and go from there. Ive already replaced some ?able vac lines and pcv. If this dont work- I already was goin t take it to a mech for a 75$ diagnostic for a whell speed sensor and evap check- the shop will figure it out

Sometimes a vacuum leak will manifest itself as a bad MAF, sometimes a dying O2 sensor or bad exhaust leak will also throw a MAF code.

possibly dieing o2. it does have alot of miles. i wanted to get a new one any way cause i hear that it wont throw a code even if it is already dead

How will a dead or dieing o2 cause a MAF code???

curious riv wrote:

How will a dead or dieing o2 cause a MAF code???

The engine could be thinking it sees a lean condition, and no matter how it tries, it's still lean, and eventually throws a MAF code. Not saying this is your problem, but it can happen.

I"ve read all over the internet about the p0102 code. And the are a million possibilities to why it comes up. I need a 02 anyway. That will be one more thing out of the way, and one step closer to getting this thing fixed. WOULD MY GUTTED AIRBOX CAUSE THIS CODE(P0102- mass air flow circuit low voltage) TO COME UP????

Only if you over-oiled an oilable filter, and the MAF sensor has an oil slick on it.  Otherwise, I doubt it.  Many of us are running modified intakes without a problem.

Just curious, did you remove the 'honeycomb' that's in the throttle body before the MAF sensor?

No, its still in there