TDI mod experiance?

[oprn]

I have two '02 TDIs that are down a bit on power. It seems the EGR system is responsible for this at times and needs regular cleaning. I see some people delete this system. Who has experiance with this and what are the pitfalls?

Thanks in advance.

[TDCTDI]

"Regular cleaning" is roughly 100,000 miles before there's any noticeable decrease in performance. You can do a EGR delete but by the time you do the block off, re-plumb the coolant lines, & pay for a tune that deletes the EGR function to keep the light off, UNLESS the cooler takes a shit, it seems like wasted money.

You can adjust the parameters so that the EGR effectively never comes on & leave it all in place.
_________________
Everybody born before 1975 has a story, good, bad, or indifferent, about a VW.


GOFUNDYOURSELF, quit asking everyone to do it for you!


An air cooled VW will make you a hoarder.


Do something, anything, to your project every day, and you will eventually complete it.

[Butcher]

[oprn]

Looks a bit harsh. No danger of warping the manifold?

[TDCTDI]

[oprn]

Ok Thanks!

The Jetta was into a shop just a few months back to have this intake clogging problem looked after. Not a VW dealer but a European car shop that does a lot of VWs and sells air cooled parts too. My daughter has been driving this car to collage for the last 2 years in the city so I have not been driving it or close enough to over see the maintenance.

This weekend we had possession of the car and drove it about 900 miles and I now have a better feel for what it's running like and have doubts about the EGR valve being the problem. Here is what it is doing.

When you got through the gears it pulls hard for about 3 seconds in every gear and then goes flat. If you then leave your foot into it and wait, after 8 to 10 seconds it slowly gains power again until it seems to be pulling about normal. If you are cruising at a steady speed and go to pass it does the same thing, 3 seconds of good power, goes flat and then a slow steady gain back to good power.

I tried it out on a long river hill, rolled the power on as I pulled out into the passing lane and it gave the usual burst, went flat, then slowly started to pull again. It held good power for the rest of the hill passing everything other car there.

I put a new fuel filter in it already so that is not the problem. Ideas? Vacuum leak? Sticky waste gate? Turbo clogged with carbon?

[TDCTDI]

This going into limp mode can be caused by several things. Most likely you have a vacuum leak somewhere.
_________________
Everybody born before 1975 has a story, good, bad, or indifferent, about a VW.


GOFUNDYOURSELF, quit asking everyone to do it for you!


An air cooled VW will make you a hoarder.


Do something, anything, to your project every day, and you will eventually complete it.

[oprn]

Thanks again.

No check engine light, should there be?

[TDCTDI]

With no check engine light (although codes may be stored ), it could be a MAF sensor. Just about the only thing that does not trigger a code is the damned MAF sensor.

There again, scan the DTC memory & check for vacuum leaks before throwing parts at it. But you could swap from your other car to check.
_________________
Everybody born before 1975 has a story, good, bad, or indifferent, about a VW.


GOFUNDYOURSELF, quit asking everyone to do it for you!


An air cooled VW will make you a hoarder.


Do something, anything, to your project every day, and you will eventually complete it.

[Butcher]

Not a bad idea to replace the fuel filter if you do not know when it was replaced last.

[oprn]

[oprn]

[Butcher]

[TDCTDI]

[oprn]

Ok I will give it a go. I have some busy days coming up so not likely until the weekend.

Thanks again!

[oprn]

Finally work slowed down enough to get a day off. Did some checking, the vacuum pump gives me -18"Hg right on start up and settles down to -23"Hg very soon after. There are 3 vacuum pots, one on the turbo waste gate, two up on the EGR valve body. All held vacuum and I observed motion on all 3. The hose down to the waste gate pot is frayed and will be replaced but again for now it holds a vacuum.

There are also 3 units that I would call solenoids but most likely have another proper name that I think convert the signal from the brains of this system to a vacuum signal to put these pots in motion. Not sure how to test them yet.

Tomorrow I will attempt to use my code reader and see if I learn anything.

TDCTDI, where is this MAF sensor you speak of? I have the other car in the yard now so I could swap them and see if the problem follows. Thanks!

[oprn]

Got the code reader working - no codes. Found the MAF sensor, switched it with the one from the other car. Running GREAT now! Problem found! I will clean this faulty one up and see if it works again. Seems to have a bit of black soot on it.

[oprn]

Cleaned up the sensor and put it back in, all good!