150 bhp tdi power problem

[princebishop]

I have noticed numerous threads with MK4 TDI's and a loss of power. I have a low miler which kindly decided to fail to pull one morning last week. Coming out of traffic on a dual carriage way (all ok on slip road etc) I put my foot down and nothing happened at all. It felt like I was in too high a gear with far too low revs - so I changed down and whilst it rev'd high in 4th it just didn't pull at all - no turbo or even acceleration. I was running low on diesel and the light had just come on - so pulled over, refuelled and all was as it should be!?!

Has only happened the once, but the car when started a couple of times has rev'd highly (as if I had foot down on accelerator pedal).

Is this the same problem as the other power loss threads? any advice would be fantastic as the main dealer found no problems when they ran a diagnostic check.

[chris.fulton]

This is a very common problem with the VAG engines and the problem usually is either the MAF or the turbo. The car will suddenly lose power in 4th, 5th or 6th gear at high revs and once the engine is restarted the power returns. Normally MAF faults don't log a fault code and turbo problems do log a code. Since you say there were no fault codes found then hopefully it's just a faulty MAF. Disconnect it and run the car at high revs in a high gear and hopefully the car should run fairly normally, if not a little down on power. This would then suggest the MAF is faulty and you should replace it. They cost around £70 from VW dealers and are very easy to replace. If that doesn't work then there's something wrong with the turbo or one of the associated parts.

Also, welcome to the forum

[mobitune]

the car when started a couple of times has rev'd highly (as if I had foot down on accelerator pedal).


This happened mine (Intermittently) when the coolant sensor went faulty. Could be you have two problems, this and the one Chris has mentioned above.

Get someone with vag-com to check for faults, much cheaper than a trip to the VW main ***********

[princebishop]

Thanks for your advice, much appreciated.

The diagnostic check did bring up two faults - one being the cooling fans and fuse being not working as intended, the second being the temp sendor. Looking at getting these done soon, will the temp sendor be the same as the coolant sensor? Will ask the garage to unplug the MAF and see what happens