MAF g/s issue

[eltonbien]

Hi All,

Need help with some issue with my stage 2 giac, mk6 gti 2010.

for a long time now my fuel trim was around -16 ltfm
then one day the car struggle in low gear between 1st and 2nd gear and then would spew white smoke and would later go away just as fast as it came.
I could not replicate the circumstance except i noted it would struggle in low gear and later would spew white smoke.

I read in the TDI forum that it may be related to vacuum leak which may could well be, but i went around to check for tell tale sign of any oil build up in all the pipes and found nothing, did my own smoke test and did not show any leak that i could spot.

I bought a ross tech micro can and scanned the car.

so between 1k to 4k rpm the MAF g/s would only reach above 100 g/s on occassion and not consistent. and the fuel trim is still on -16 LTFT

my car is GIAC stage 2 and has CTS Turbo Cold Air Intake, coil pack and turbo back exhaust.

today i removed the intake and replaced it with my stock.

and bought a second hand maf sensor to see if my old maf is causing the low g/s.

after the install back to OEM, the car became responsive again, no more lag on low gear, i have yet to see the white smoke (finger cross) but when i scanned it. the MAF g/s is still way below what i see as normal or in comparison to other cars and the LTFT went down to -13.7

am i missing something? I know the normal range for MAF g/s is between 180 to 200+ on normal circumstances. but mine is not hitting that and not even seen it hit 200 g/s since i started scanning it.

I have been having this issue for a while now and would really need your help to solve this problem of mine.

thanks in advance.

[Milos504]

Hi All,

Need help with some issue with my stage 2 giac, mk6 gti 2010.

for a long time now my fuel trim was around -16 ltfm
then one day the car struggle in low gear between 1st and 2nd gear and then would spew white smoke and would later go away just as fast as it came.
I could not replicate the circumstance except i noted it would struggle in low gear and later would spew white smoke.

I read in the TDI forum that it may be related to vacuum leak which may could well be, but i went around to check for tell tale sign of any oil build up in all the pipes and found nothing, did my own smoke test and did not show any leak that i could spot.

I bought a ross tech micro can and scanned the car.

so between 1k to 4k rpm the MAF g/s would only reach above 100 g/s on occassion and not consistent. and the fuel trim is still on -16 LTFT

my car is GIAC stage 2 and has CTS Turbo Cold Air Intake, coil pack and turbo back exhaust.

today i removed the intake and replaced it with my stock.

and bought a second hand maf sensor to see if my old maf is causing the low g/s.

after the install back to OEM, the car became responsive again, no more lag on low gear, i have yet to see the white smoke (finger cross) but when i scanned it. the MAF g/s is still way below what i see as normal or in comparison to other cars and the LTFT went down to -13.7

am i missing something? I know the normal range for MAF g/s is between 180 to 200+ on normal circumstances. but mine is not hitting that and not even seen it hit 200 g/s since i started scanning it.

I have been having this issue for a while now and would really need your help to solve this problem of mine.

thanks in advance.

Did the problem go away straight after the intake removal, or after new MAF?
I'd try the engine cover with your original MAF. If it's fine then it must be the intake, reinstall it, try again.

[eltonbien]

Ill try and reinstall the old maf and do a scanned run later today after work and see how I go.

[eltonbien]

Problem fixed.
Read from a forum not related to vw that a faulty pcv can cause the maf sensor to under report.
My pcv didnt show any usual sign it was faulty. No error code no wistling. Took the gamble and bought a new one. Now the car kicks hard.