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nas179 so i tried looking around for some experience with the p0100 cel, but haven't found a whole lot of specifics (just one guy saying that the maf had a bad ground and the dealership cleaned it up for him.) i guess the reason i'm asking is because i'm a bit confused by it. so it's a mass air flow issue, that much i know. it started when i put the pflow intake in. i expected it to come n, but i also expected it to relearn the air flow and go out with the rest of the cels that came up. sure enough, all of them but the p0100 cleared themselves... what's weird though, my car doesn't run any rougher than it ever did. i haven't noticed any mileage drop either, which i'm pretty sure both would be the case with most bad maf issues. i pulled the maf out and the filament inside looked fine, so i'm a bit lost as far as what it could be. from what i know there's a part in the maf that heats up, and it takes more or less air to cool the heated part. depending on whether the piece is too warm or too cold, different voltage is sent to the ecu and a cel is thrown at different thresholds... so i guess my question is, if the filament inside is ok, would it maybe be a problem with the electronic end of it all? any thoughts or experience before i talk to a dealership? #1 · Feb 9, 2011 so i tried looking around for some experience with the p0100 cel, but haven't found a whole lot of specifics (just one guy saying that the maf had a bad ground and the dealership cleaned it up for him.) i guess the reason i'm asking is because i'm a bit confused by it. so it's a mass air flow issue, that much i know. it started when i put the pflow intake in. i expected it to come n, but i also expected it to relearn the air flow and go out with the rest of the cels that came up. sure enough, all of them but the p0100 cleared themselves... what's weird though, my car doesn't run any rougher than it ever did. i haven't noticed any mileage drop either, which i'm pretty sure both would be the case with most bad maf issues. i pulled the maf out and the filament inside looked fine, so i'm a bit lost as far as what it could be. from what i know there's a part in the maf that heats up, and it takes more or less air to cool the heated part. depending on whether the piece is too warm or too cold, different voltage is sent to the ecu and a cel is thrown at different thresholds... so i guess my question is, if the filament inside is ok, would it maybe be a problem with the electronic end of it all? any thoughts or experience before i talk to a dealership? Sort by Oldest first Oldest first Newest first Most reactions #2 · Feb 9, 2011 sometimes intakes screw with the maf. first thing i would do is disconnect the battery for 10 mins. get some MAF cleaner(not brake clean!!!) and spray the hell out of it. sometimes the air filter oil gets on the maf and screws with it. if that doesnt help ur MAF is probably bad. but u can try swapping with another 2.0t owners MAF and see if it works, if so then u know what u need #3 · Feb 9, 2011 I'd go have that checked out because when I put my p flow on then it never threw any lights or codes and the MAF worked fine the whole time. You may have a bad MAF that could be clogged up or some loose wires maybe? Do you have a dryflow filter or an oiled neupseed filter? #4 · Feb 9, 2011 i'd tend to think it was my maf that's gone bad too... however... it runs fine. if a maf is bad usually it hesitates, gurgles, all sorts of fun stuff. that's why i'm confused. it runs fine. just throwing a cel. #5 · Feb 9, 2011 actually, not sure on what kind of filter it is... i had an old car with a k&n filter and it was the oiled one, this guy looks teh same, so i'd assume it's the oiled one. just came out of the box and i never really took notice. just red with the metal mesh around it. didn't feel if it was oily when i put it in. #6 · Feb 9, 2011 You might go check that to see if by a slim chance that some of the oil from the filter seeped through the pipe and has got in your MAF. I have the oiled filter but I have never had any problems with it so I am unsure of what it is. Maybe your fittings have come loose or three is a hole in the silicone fitting that goes into the turbo. #7 · Feb 9, 2011

nas179 said: i'd tend to think it was my maf that's gone bad too... however... it runs fine. if a maf is bad usually it hesitates, gurgles, all sorts of fun stuff. that's why i'm confused. it runs fine. just throwing a cel. Click to expand...

thats not always true. sometimes it gets dirty and throws it off what it should be reading, but doesnt throw a light cause its still within its resistance limits. ive had to replace MANY MANY things that were bad but never threw a code. #8 · Feb 9, 2011

Black_Bunny said: thats not always true. sometimes it gets dirty and throws it off what it should be reading, but doesnt throw a light cause its still within its resistance limits. ive had to replace MANY MANY things that were bad but never threw a code. Click to expand...

i agree with that, but it's the opposite going on. that would be like saying replacing a cam follower that was bad didn't throw a cel... you would never get a cel for that because the car has no idea what the follower is like, it's not hooked up to the ecu. like i said, if a maf is bad, you should know because it's causing the car to do something strange or just run differently. i've never heard of a maf going bad and not making the car run like ass. it's not. it runs fine. i'm not saying it's NOT the maf, i just can't understand why it would throw a code without anything seeming to be wrong with the car. and like i said before, the maf itself looks fine. i pulled it, looked at it, blew it out, and saw nothing on or near the sensor itself. it's pretty clean. #9 · Feb 10, 2011 ok ill give u a story. im a mechanic and i usually do the trouble shooting and drivability problems. i had a ford come in that was running rich cause it was throwing a code for rich mixture. i checked a lot of things! from compression to maf, to plugs and coils, and o2 sensor. it ended up being the maf even thou the truck was running perfectly fine. it wasnt dirty but something happend to it that i couldnt explain. either way once i replaced it the fuel trim went back to what it was supposed to. had another ford that was having trouble idling but no codes. hooked it up to my new better scanner that can read real time parameters. found out it was the throttle body itself cause it doesnt have a idle motor it uses the thottle body to control the idle itself. so the point im getting at is it doesnt have to throw a code to be bad. some cars if one sensor goes bad it will stop reading from that sensor and either go off a pre-determined value set from the factory or will read of a similiar sensor i.e. if maf sensor is bad it will rely on throttle position and or map but u will never notice anything wrong. think about it also u said it threw a code after u installed your intake. what else do u think it could be lol #10 · Feb 10, 2011 I honestly think that this problem could be with the ground on the MAF sensor as some others have had this problem and taken it to VW and they have replaced it. Could check it out. #11 · Feb 11, 2011

Black_Bunny said: ok ill give u a story. im a mechanic and i usually do the trouble shooting and drivability problems. i had a ford come in that was running rich cause it was throwing a code for rich mixture. i checked a lot of things! from compression to maf, to plugs and coils, and o2 sensor. it ended up being the maf even thou the truck was running perfectly fine. it wasnt dirty but something happend to it that i couldnt explain. either way once i replaced it the fuel trim went back to what it was supposed to. had another ford that was having trouble idling but no codes. hooked it up to my new better scanner that can read real time parameters. found out it was the throttle body itself cause it doesnt have a idle motor it uses the thottle body to control the idle itself. so the point im getting at is it doesnt have to throw a code to be bad. some cars if one sensor goes bad it will stop reading from that sensor and either go off a pre-determined value set from the factory or will read of a similiar sensor i.e. if maf sensor is bad it will rely on throttle position and or map but u will never notice anything wrong. think about it also u said it threw a code after u installed your intake. what else do u think it could be lol Click to expand...

like i said, i'm not ruling out the maf, it could be bad, but i've never really heard of a maf going bad and not seeing something run differently in the car. not even mileage. and yeah, of course something can be bad and not throw a code. i'm not arguing you there either. i'm just saying if something as big as a maf is bad, i'll almost guarantee you'll notice something wrong. mileage, rough idle, throttle response... something, anything. personally, i think it is a ground or something electrical on the maf sensor. i'll have some time tomorrow to check it out after work, so i should have some answers then. #12 · Feb 11, 2011 Well if the duster can doesn't do it just huff the rest of it. #13 · Feb 11, 2011

nas179 said: like i said, i'm not ruling out the maf, it could be bad, but i've never really heard of a maf going bad and not seeing something run differently in the car. not even mileage. and yeah, of course something can be bad and not throw a code. i'm not arguing you there either. i'm just saying if something as big as a maf is bad, i'll almost guarantee you'll notice something wrong. mileage, rough idle, throttle response... something, anything. personally, i think it is a ground or something electrical on the maf sensor. i'll have some time tomorrow to check it out after work, so i should have some answers then. Click to expand...

well u havent been around enough cars then. most newer cars like yours like i said will stop reading from that sensor and read from another sensor hence like a map sensor. im pretty sure those 2.0t's use a map too and a map sensor is the same thing as a maf. some cars use both sensors to be very accurate or if one fails it will rely on the other. newer cars these days have to be very strict with emissions and that requires more sensors doing more work. #14 · Feb 12, 2011

xcrazydx said: Well if the duster can doesn't do it just huff the rest of it. Click to expand...

haha, done and done... made me forget about the cel for a little bit anyway #15 · Feb 12, 2011 so i sprayed the maf out with the cleaner... i think it was crc maf cleaner? can't remember the name brand, but advance auto carries it. good stuff. we use the same stuff for cleaning electrical boards basically... anyway, specifically sprayed the sensor end of it, with the filament only, i purposely skipped the electronics end of it just to see what it was. so after spraying the sensor and filament, put it back on, cel came up. cleared it, shut don, started up, revved, cel again. on to step 2. pulled the electronic clip this time only, and sprayed it out, not touching the sensor at all. plugged it back in, turned on, cleared cel, revved, shut down, started up, no cel. so it was the electronic end of the sensor, not the filament itself. i'm guessing somehow some oil or something got into the actual plug at some point when i was changing the intake out and it wasn't making great contact inside the plug, hence the cel without poor performance. also why it was working fine but putting up a code. kinda just a guess at this point, but at least i confirmed what i thought in the first place and that the maf was fine. long story short, maf sensor cleaner is awesome, just wouldn't recommend getting a ton of overspray on your hands unless you're going for the zombie white skin look. haha #16 · Feb 12, 2011

nas179 said: so i sprayed the maf out with the cleaner... i think it was crc maf cleaner? can't remember the name brand, but advance auto carries it. good stuff. we use the same stuff for cleaning electrical boards basically... anyway, specifically sprayed the sensor end of it, with the filament only, i purposely skipped the electronics end of it just to see what it was. so after spraying the sensor and filament, put it back on, cel came up. cleared it, shut don, started up, revved, cel again. on to step 2. pulled the electronic clip this time only, and sprayed it out, not touching the sensor at all. plugged it back in, turned on, cleared cel, revved, shut down, started up, no cel. so it was the electronic end of the sensor, not the filament itself. i'm guessing somehow some oil or something got into the actual plug at some point when i was changing the intake out and it wasn't making great contact inside the plug, hence the cel without poor performance. also why it was working fine but putting up a code. kinda just a guess at this point, but at least i confirmed what i thought in the first place and that the maf was fine. long story short, maf sensor cleaner is awesome, just wouldn't recommend getting a ton of overspray on your hands unless you're going for the zombie white skin look. haha Click to expand...

Cool, good job. #17 · Feb 12, 2011 and you didnt want to believe me lol. well atleast u didnt need a new one and its fine #18 · Feb 13, 2011

Black_Bunny said: and you didnt want to believe me lol. well atleast u didnt need a new one and its fine Click to expand...

it wasn't that i didn't want to believe you at all... i just knew that there was nothign really wrong with the sensor itself... i think from one of my first posts i thought it was an electrical issue (more specifically a ground issue on the maf plug) which is exactly what it seems to have been. the sensor itself is fine and didn't even need to be cleaned, it was the plug. Insert Quotes Post Reply

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