Premature MAF Sensor Failure?

Thanks good info. I must control my paranoia. Actually, I did give the sensor a blast of CRC at 50k just for preventive maintenance. Perhaps time for another. Thanks for your response!
hey no problem.. ya there are lots of shady people in the auto repair business it's good to be paranoid! it helps! ya might be dirty again.. if you do find it's dirty let us know! probably why the check engine light was on.
 
Maf question. I have a Nissan Versa 1.6L. Just turned 100k. Has never set a code. The other day went for an oil change. When I started the car to drive off my first check engine light appeared. Went back inside, asked the tech to read it on the spot. Maf code popped out. He said “ I can clear it but it”l just come back. My question is, can a tech deliberately do something to trigger that sequence of events or was this the mother of all coincidences? I’m old, and slightly OCD. Give it to me straight. Car runs fine, air filter changes kept up, 3 weeks later code has not returned.
Did the code come back yet? Disturbing it really shouldn't throw a code? The little wire is inside a metal housing inside the intake duct. Moving it around shouldn't matter.

Its possible he disturbed the connector. You may wish to re-seat the connector - its typically on top the air intake duct not far past the air filter.

Might just need cleaning. Or the wire may have been broken somehow, but the tech would likely need to work at it to break it. Like sticking a screwdriver inside the metal housing. It looks like this - and the only part that sticks out is the connector portion

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Did the code come back yet? Disturbing it really shouldn't throw a code? The little wire is inside a metal housing inside the intake duct. Moving it around shouldn't matter.

Its possible he disturbed the connector. You may wish to re-seat the connector - its typically on top the air intake duct not far past the air filter.

Might just need cleaning. Or the wire may have been broken somehow, but the tech would likely need to work at it to break it. Like sticking a screwdriver inside the metal housing.
No code yet. A little weird, we’ll see what happens. Did my oil changes myself for years, but now I live in a nosy 55 and over. If my neighbors see my legs sticking out from underneath my car I guarantee you somebody will call 911.
 
No code yet. A little weird, we’ll see what happens. Did my oil changes myself for years, but now I live in a nosy 55 and over. If my neighbors see my legs sticking out from underneath my car I guarantee you somebody will call 911.
No code, no reason to worry. If it stops working it will throw a code immediately.
 
We have had absolutely terrible luck with aftermarket MAF sensors at the shop. Used to be we would only use Delphi MAFs if we were going aftermarket, or in some situations Napa's Altrom line would have Hitachi available. Delphi changed their design to be similar to the Echlin/Standard/Name Your Brand aftermarket sensors, the only two I tried after the change didn't work right out of the box. Finally gave up and went to OE, save for the vehicles that take the Hitachi that is about as close to OE as you can get. Not a problem since.
So we can't even trust Delphi any longer. SMH.
 
Ok, school me, how would a dirty old air filter make a difference to the MAF? I’m under the impression a dirty filter works better than a clean one?

I have a Wix in there now. The same one I put in back when the original MAF died a couple years ago. Guess I’ll order a Motorcraft one and swap it out. Actually costs me less than Wix. Lol.
Semi-related. My new 2014 Nissan Rogue Select killed it's MAF in short order.

Took me a while to find the reason. In disassembling the airbox I later noticed the factory spun polymer fibre air filter was soaked in oil. I replaced it with a budget STP. I put the O.E. filter in the STP box tossed it in the tire well in the boot. It ended up being saturated with oil leaching from the factory filter!. This was not a PCV or oil overfill issue. It was a filter factory QC issue.

I Removed the MAF and spritzed it thoroughly with CRC MAF cleaner and all was well after a few hours of relearning.

But the catcon must of took some bad fueling in enrichment mode and was acting clogged. I think I was able to drive that out after a week of some hard interstate on-ramp acceleration.

Just a note, out family's Subaru all have have a pretty substantial secondary non-replaceable filter panel in front of the MAF.

I say lambda controlled FI systems are a bad design, They take 02 sensing and MAF at face value. and can run horribly. I think the software is written to avoid lighting a MIL unless there is an outright component failure - at least on most commodity passengers cars.

The you point Dirty AF likely just impeded airflow by throttling the engine. Possibly resulting in BETTER fuel economy.
 
I say lambda controlled FI systems are a bad design, They take 02 sensing and MAF at face value. and can run horribly. I think the software is written to avoid lighting a MIL unless there is an outright component failure - at least on most commodity passengers cars.
The control system adjusts fuel trims based on the primary A/F sensor downstream closing the loop, so there not taking the MAF sensor at face value. Dirty MAF sensor in the end wouldn't likely matter that much for most people, and a dirty MAF sensor likely wouldn't improve mileage. Some control systems compensate the primary A/F sensor with the secondary 02 sensor, but at that point your usually way out in the weeds anyway so how much it helps I don't know.

Your correct in that control system won't light a MIL until long term fuel trims are either 20 or 25%, which I agree is likely too much. Of course if they did it earlier you would have lots of people failing emissions for it and no one would be happy with that.

Not sure if a MAP or MAF is better - the MAF is supposed to be better with pressure and altitude changes. How so I have no idea. Someone here told me some vehicles have both - but I have never owned one that does.
 
Not sure if a MAP or MAF is better - the MAF is supposed to be better with pressure and altitude changes. How so I have no idea. Someone here told me some vehicles have both - but I have never owned one that does.

Yes, some use both and the MAP is usually the more expensive of the two. The MAP does not include an IAT sensor like some MAF.
 
The control system adjusts fuel trims based on the primary A/F sensor downstream closing the loop, so there not taking the MAF sensor at face value. Dirty MAF sensor in the end wouldn't likely matter that much for most people, and a dirty MAF sensor likely wouldn't improve mileage. Some control systems compensate the primary A/F sensor with the secondary 02 sensor, but at that point your usually way out in the weeds anyway so how much it helps I don't know.

Your correct in that control system won't light a MIL until long term fuel trims are either 20 or 25%, which I agree is likely too much. Of course if they did it earlier you would have lots of people failing emissions for it and no one would be happy with that.

Not sure if a MAP or MAF is better - the MAF is supposed to be better with pressure and altitude changes. How so I have no idea. Someone here told me some vehicles have both - but I have never owned one that does.
If it narrowband lambda? That only operates at light throttle cruise and idle and no enrichment. Offset data would be stored if the trim is off like you stated, and again typically NO mil lit in commodity product which is criminal in my book. And the Lambda is taken at face value which has been a massive implementation error only somewhat addressed with post cat sense.
All of the OBDii engines I've worked on have MAF and MAP. Mainly NA subaru.
 
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Maf question. I have a Nissan Versa 1.6L. Just turned 100k. Has never set a code. The other day went for an oil change. When I started the car to drive off my first check engine light appeared. Went back inside, asked the tech to read it on the spot. Maf code popped out. He said “ I can clear it but it”l just come back. My question is, can a tech deliberately do something to trigger that sequence of events or was this the mother of all coincidences? I’m old, and slightly OCD. Give it to me straight. Car runs fine, air filter changes kept up, 3 weeks later code has not returned.
Make sure they buttoned up the filter box. almost ALWAYS the lube joints and dealers don't get it right.. It the lube joint if you refuse an air filter change they just throw the parts under the hood. Happened more than once.
 
Now my question is… why did this sensor last such a short period of time? Does having the key on with the engine off cause it to overheat? I understand that MAF sensors work using heat, and I wonder if with no airflow over it, it kills it? I do have the key on with engine off quite often, sometimes for an hour…
That's a distinct possibility.
 
Now my question is… why did this sensor last such a short period of time? Does having the key on with the engine off cause it to overheat? I understand that MAF sensors work using heat, and I wonder if with no airflow over it, it kills it? I do have the key on with engine off quite often, sometimes for an hour…
My understanding is thats not how they work. They maintain the wire at a constant temperature - and measure the current required to keep it at that temperature. The more air flowing by, the more current required to maintain whatever temperature they are at. Thats how the ECU knows the air flow (along with knowing the inlet air temperature)

Presumably with no air flow they would still be at the same temperature?
 
Yes, some use both and the MAP is usually the more expensive of the two. The MAP does not include an IAT sensor like some MAF.
My '11 Chevy 5.3 has both, IAT in the MAF also. I chased I/M monitors not running due to a erratic non code setting MAP. Only way I caught it was my Autoenginuity has 2 MAP tests in it and one test erratically would show failure. New MAP fixed it and got back 3 mpg highway also.
Another tip off was real time dash MPG gauge would not go to it's maximum reading off 99 MPG on downhill off throttle coasting. Would erratically bounce around at lower readings. The more expensive MAP was the cure.
 
No code yet. A little weird, we’ll see what happens. Did my oil changes myself for years, but now I live in a nosy 55 and over. If my neighbors see my legs sticking out from underneath my car I guarantee you somebody will call 911.
Well. The code reset. Again just after the oil cooler o ring was replaced for the second time.And I mean as SOON as the oil cooler o ring was replaced. I pulled the MAF, sprayed it liberally with Maf cleaner , and re-installed. We’ll see if it responds to a drive cycle (Regarding the check engine light). It APPEARS to be running better with less “hunting” for a proper rpm. It’s a 1.6 Nissan Versa. FWIW the aftermarket oil cooler 0 ring appears to be a little skinny in thickness compared to the OEM. I can say that the annoying oil leak has stopped after the thicker oil cooler O ring was installed. As to what the correlation is from an oil change /oil cooler issue that could trigger a MAF code I’d like to know.
 
Well. The code reset. Again just after the oil cooler o ring was replaced for the second time.And I mean as SOON as the oil cooler o ring was replaced. I pulled the MAF, sprayed it liberally with Maf cleaner , and re-installed. We’ll see if it responds to a drive cycle (Regarding the check engine light). It APPEARS to be running better with less “hunting” for a proper rpm. It’s a 1.6 Nissan Versa. FWIW the aftermarket oil cooler 0 ring appears to be a little skinny in thickness compared to the OEM. I can say that the annoying oil leak has stopped after the thicker oil cooler O ring was installed. As to what the correlation is from an oil change /oil cooler issue that could trigger a MAF code I’d like to know.
The car has 100k on it. MAF has been cleaned once at 50k. Maybe I gotta get more pro active.
 
No you cannot, the aftermarket world has become a very sketchy place. For most sensors and coils I use OE only, O2 sensors manufactured by well known brand names still seem okay.
I understand Hitachi was OEM for general motors mass airflow sensors.
I don't need one right now but sometimes I look for parts and write the numbers down so in case I would ever need it I'll know the numbers and everything.
I can't even find Hitachi for the 01 Grand Prix with a 3.1.
Looks like the general motors MAF is close to $200 for that car.
 
I understand Hitachi was OEM for General Motors mass airflow sensors.
I don't need one right now but sometimes I look for parts and write the numbers down so in case I would ever need it I'll know the numbers and everything.
I can't even find Hitachi for the 01 Grand Prix with a 3.1.
Looks like the General Motors MAF is close to $200 for that car.
Found a nice Hitachi Parts PDF. May be helpful to some!
Looks like they don't even show a MAF sensor for my car.

 
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