GolfGTIforum.co.uk

Model specific boards => Golf mk4 => Golf mk4 TDI => Topic started by: yourloveismydrug on 05 June 2012, 13:55

Title: 2003 Tdi 150 black smoke , hesitant throttle
Post by: yourloveismydrug on 05 June 2012, 13:55
A fortnight back I removed inlet and EGR and cleaned them both , replaced all vacuum pipes and fitted new vacuum reservoir (broke the first myself ) Replaced fuel filter and fitted new genuine bosch MAF , car has run great since until yesterday (maybe )

The car belongs to my Mrs and today I drove it and notice at a particular point low down in the revs it would miss , I tried it a few timesand sure enough when I would try and hold the throttle at around 1800 RPM  approx it would miss , I noticed at the same time puffs of black smoke which got bigger the more I did it until it was pretty bad and power was almost non existent.

The car starts and idles fine , the engine sounds good and does boost but its getting worse .

NOw by my reasoning , the black smoke would suggest unburnt fuel and the hesitancy at low revs would suggest to me it isn't the turbo (hopefully)  .  I am thinking throttle position sensor/pedal box . suggestions please .

I am about to put it up on ramps and check the pipes and turbo.... 

thanks in advance
Title: Re: 2003 Tdi 150 black smoke , hesitant throttle
Post by: yourloveismydrug on 05 June 2012, 14:19
forgot to mention fuel  economy has been noticeably down , for istance , filled the tank and usually round town she would get easily over 200 miles but barely 150 miles .

have just unplugged the MAF and took it for a drive and although no power there was also no smoke or missing .

Pipes are all stilll attached and no tears apparent .

so I'm now thinking MAF
Title: Re: 2003 Tdi 150 black smoke , hesitant throttle
Post by: Rhyso on 05 June 2012, 15:35
My money is on a boost pipe popping / slightly off on the intercooler.

Id be checking the boost pipes before claiming a problem with the maf  :smiley:
Title: Re: 2003 Tdi 150 black smoke , hesitant throttle
Post by: scarr89 on 05 June 2012, 21:28
My money is on a boost pipe popping / slightly off on the intercooler.

Id be checking the boost pipes before claiming a problem with the maf  :smiley:

This.

If you removed the MAF sensor and it drove worse then it probably isn't the MAF. Check the boost pipes, even if they are hanging out, and disconnected slightly you will know about it!