Another low power, - yes, I have tried everything...

[ShaferDiesel]

I have a customers 99 Jetta TDI in my shop, and I guess I'll give ya the whole story.

Car came to me 3 months ago for low power. I swap MAF, Set IQ, set timing, Clean VGT, clean intake, already has EGR delete, swapped N75, Vacuum test VGT actuator (hand held vac pump while driving) VGT moves freely and with correct travel. No exhaust or intake leaks. I can NEVER get more than 1400 mBar MAP. Removed CAT, same prob. So I play with this thing for 2 weeks and the customer get impatient and takes it to the dealer "who knows what they're doing". (btw, this has been a good long time customer!) I don't hear anything for a long time about it.

Then I find out that dealer reflashed the ECM, did a compression check, replaced MAF, replaced the TPS, replaced turbo, and who knows what else. They had the car for 7 weeks, and finally gave up.

Now the car is back at my shop, I'm going to try swapping the MAP sensor tonight even tho it reads 1003 mbar with engine off, and a max of 1400 with a nice smooth sweep. Next I'll swap ECMs, and then what?

I've read the whole low power, limp mode, uncommon low power, the whole d@%m internet, etc.

Car used to have Kerma's tune, but that's gone after the dealer got ahold of it.. Maybe I'll just have jeff at rocketchip flash it and cover up the problem for them

I'm just pulling my hair out, any ideas?

[Seatman]

Is it coming up with specific fault codes? The car runs sweet but just lacks oomph?
Does it rev up no bother?
Dealers, no wonder they get a bad name and that must've cost a fortune too.

[ShaferDiesel]

Absolutly no codes. And a little more info that I forgot in the last post.

This is NOT limp mode
Step on pedal, feels like it's gonna really get on with it for just a sec, than it looses it and feels like lower power than limp mode, back off pedal, and in picks up just a little.
When foot is down, it does put out a slight haze of black smoke, and when I romp on it in the shop it puts out good little black puffs.
Injector pump was replaced 1 year ago for a legit problem with it
No air bubbles in fuel, good flow, and even tried a dodge lift pump.
Starts and runs smooth and sweet.

[Seatman]

How are the small vacuum pipes? have they been replaced at all, the black smoke to me suggests to much fuel but I'm no expert so could be talking bull, do you know if it's had bigger nozzles fitted too? I've only ever had a similar throttle feel when my car was heading for limp mode but after I stripped and cleaned everything and replaced all the vacuum pipes (wether they looked bad or not) it's been great but you're saying all the cleaning stuff has been done so if the vac lines haven't been changed it might be worth a shot as they're really cheap and easy to do. It might be worth checking ecm/ecu is nice and dry too because mine was soaked through when I got my car and it gave me a few problems but was fine once dried out and resealed. I don't know what else to suggest at the moment and can understand why you're stuck.

[don beard]

just had inner cooler pipe gasket fail,(according to dealer) it acted similiar

[Seatman]

Hi there don beard and

[almir]

Hi, when you are looking at the live data on the scanner, what are you getting for TPS position in %? is it smooth increase or does it suddenly decreases then increases?

[ShaferDiesel]

Originally Posted by almir

Hi, when you are looking at the live data on the scanner, what are you getting for TPS position in %? is it smooth increase or does it suddenly decreases then increases?

Smooth to 100%, and the dealer replaced it anyway

[ShaferDiesel]

Originally Posted by don beard

just had inner cooler pipe gasket fail,(according to dealer) it acted similiar

Not here, the whole intake system is airtight except for the PCV

[Seatman]

Have you gotten any further with that car yet?