Help with a3, power loss, black smoke etc

[deek19790]

Hi guys,

Been having an issue with my car for last few months as follows:

1. Feels like turbo isn't kicking in as car pickup is like none turbo.
2. When driving at high speeds 70mph sometimes the car struggles to get to 80 and feel like its stuggles at 70 but than at other times it's fine.
3. Puffs of black smoke when I put the foot down at least every two days....exhaust black on end in a week after cleaning.

i got the maf changed by a vw specialist, he ordered the whole unit but only changed the sensor, would this cause the issue as i have had an improvement since the change in terms of less smoke but power loss is still there....should the whole unit have been changed and also whats chances of faulty sensor?

i have checked the silicone pipes coming off the turbo to the intercooler then from the IC to the inlet manifold to make sure they in fine which they are.

also the car used to hissss before when putting the pedal down but since the power loss i don't hear the hisssing at all.

i have scanned with vcds and it reported no engine faults.

speaking with someone they said it could one of these items:

1. faulty injector loom
2. egr
3. turbo itself
4. faulty replacement maf.

please could anyone help rule these out as i don't want to spend money on replacing these all one by one.

any help is appricated as im at a loss now.

thanks
d

[Doctle Odd]

I assume the MAF was genuine?

[deek19790]

hi mate,

yes i was a main dealer part but he didn't change the whole thing, he unscrewed the sensor and changed that only.

d

[Alan02]

It could be one of the problems you mentioned, but with regards to the MAF sensor, they are calibrated to the housing to which they are mounted. Fitting it to yours may not cure the problem, if in fact the MAF is faulty.

[micheal balbrig]

If your model has a load of mini rubber vacuum hoses going to solenoids etc in scuttle area,give them all a good check for leaks/security.
May be an idea also to see if anti shudder valve is working properly
Could the hissing sound have been from the wastegate valve or maybe a leak in intercooler or inlet manifold gasket. (All only possibilities and most of which would have been identified by your scan)