SEAT Leon - Seat Leon 1.9 TDI SE 110 - Lack of power - jonnyvw

I've just bought a 2002 Seat Leon TDI SE 110 and while it performed well during a test drive (around town and on a 50mph dual carriageway) I have discovered it lacks power at higher speeds. It pulls quite nicely up to about 60mph but then suddenly goes flat and doesn't want to go any further with my foot flat to the floor. I've also experienced the same lack of power/acceleration when overtaking and going up hills. This is my first TDI so I'm not really sure what to expect but this just doesn't seem right.

Also, my sister has an Audi A3 TDI that has a distinctive turbo whistle/whine but this is not noticeable on the Leon, should it be?


SEAT Leon - Seat Leon 1.9 TDI SE 110 - Lack of power - Collos25

Well its going into LHM for various reasons perhaps the EGR is blocked or not working or the turbo is US it needs connecting to the specific Seat computor to see the faults.

SEAT Leon - Seat Leon 1.9 TDI SE 110 - Lack of power - 659FBE

LHM = Limp home mode.

EGR = Exhaust gas recirculation.

US = defective...

This is a perennial defect with elderly VW group diesels and is often mis diagnosed. I would tackle this by firstly making a minute examination of all the vacuum control hoses - there are lots of them and the material VW uses is very poor. The rubber perishes under the cotton exterior.

A code scan may then tell you a little more - but a rather unhelpful "charge pressure limit exceeded" (overboost) will probably come up.

The next move is to check the actuator and variable nozzle system on the turbocharger for freedom of movement. This can be done with a length of small bore hose and a good hard suck - if you know what to look for. If you suck as hard as you can, you should be able to achieve full movement of the actuator which is about 20mm. It should move smoothly and stay fully retracted when you put your tongue over the end of the vac pipe. When you release the vacuum, it should return instantly and without sticking.

This is the most mis-diagnosed fault on VW group diesels. Don't let anyone talk you into fitting a new turbocharger without a full and reasoned understanding of what is happening. Dealers are generally useless - independent specialists much better.


SEAT Leon - Seat Leon 1.9 TDI SE 110 - Lack of power - mickeybo

Lack of power on a hill or overtaking is mostly a vacuum related (weak vac pump) the way

i would check system at vac pump theres a large vac pipe that goes to brake servo theres a small vac pipe thats teed off that supplies vac to the rest of the system. check

vac at this point reading should be approx 26/27 inhg ish using a mity vac or small vac

gauge. Then move to turbo boost solenoid remove vac pipe from input port on solenoid

attach vac gauge take reading which should read as above . Then remove vac pipe from

turbo actuator take vac reading again the best method to check out vac lines connectors

rubber elbows Hth Regards Mickeybo

SEAT Leon - Seat Leon 1.9 TDI SE 110 - Lack of power - chocka

As an quick interim solution, have you tried restarting the car? I have heard that it solves the problem, until the next time...

For the techies on this thread, I have often heard this problem is caused by sticky vanes on the turbo due to short distance running. Is there a cost effective solution if it was the cause?

SEAT Leon - Seat Leon 1.9 TDI SE 110 - Lack of power - ifekas

Over the many years I had my previous TDi (a 90bhp 1.9), I had two separate loss of power issues; the first was due to the air hose partly coming loose, causing a loss of power, but particularly at higher revs.I do remember having a similar problem to you, struggling to maintain speed on the motorway. This cost nothing to fix as it was just one of the jubilee type spring clips that had come adrift.

Years later, I had another loss of power which took ages to diagnose, but was tracked down to a blocked oxidation catalyst, which was replaced.

Oddly, although the MAF which is apparently a common cause of these issues, it never gave me problems in all the years I had the car.

On my current TDi, I do try to keep the revs up the engine when warm from time to time which should hopefully stop the oxidation catalyst from getting blocked up; thankfully it doesn't have a particulate filter!


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