Power Loss

[Jamierez]

I bought a 2001 Seat Leon 1.9 Tdi last week. Took it for its first long drive today (dropping family of at airport). Everything going fine up until approx. 30 minutes into my journey I accelerated up a hill in 5th gear and all of a sudden, it started to lose power. After that, the car struggled whilst accelerating (felt like a standard diesel!).

Car was fine when I drove away from the airport before losing power again whilst going uphill in 5th gear (again struggling with acceleration). Pulled over, switched the engine off and left it for a few minutes and the problem had gone.

For the remainder of the journey, I made sure I didn't accelerate hard in 5th gear and everything went ok.

I've done a search on the forums here and there seems a few things that it could be. So I'm after your expert advice.

 

[muddyboots]

Well first of all it sounds like your car went into limp mode - guessing it felt like the turbo had fallen off and wouldn't rev above 3000 rpm ?

If it happens under heavy load I'd guess at it being something like a boost leak or sticking turbo vanes (VNT mechanism), meaning the ECU is requesting a certain amount of boost pressure and it's either not getting enough, or too much.
Ideally you want to read the fault codes off with vag-com (post in the vag-com forum, there maybe someone local who'll help you out) as that will tell you the answer.

 

[Jamierez]

guessing it felt like the turbo had fallen off and wouldn't rev above 3000 rpm ?

Definitely feels like the turbo has fallen off, but I am pretty sure it went above 3000 rpm.

Will have a look into vagcom (first time I've heard of it).

 

[Jamierez]

My father in law is a mechanic and has worked on Volkswagens. He has suggested that the problem may lie with a blocked fuel filter. The fuel filter was supposed to be changed at the last service but wasn't. Would this be a cause of the problem?

I am going to get it changed anyway, along with the air filter as they should have been done at the 60k service.

 

[sssstew]

not that ive ever heard of. im agreeing with muddyboots here.

 

[glynnd]

Sounds like the air mass meter is on the way out. About £70 exchange to replace, they dont usually show a fault code in vag com though. The fuel filter change interval is 40k as I know

 

[sssstew]

mafs dont cause a sudden loss like this, they will just cause generally poor performance, and in-ability to rev all the time.

 

[glynnd]

Sorry I beg to differ I had similar problems till I replaced the maf!