'06 BRM 5spd Jetta

'06 BRM 5spd Jetta - intermittent driveability problems

Here's the specs:

06 Jetta TDI 5spd with 222,000km on the odometer
Stage 1.5 Malone
zip tie mod.... 100mbar delta


I'm having some driveability problems, hard to pinpoint, as some days the car seems to drive better than others. Recently I have experienced

- lumpy idle waiting at stop lights sometimes
- some exhaust smell in the cabin at stop lights. I don't notice this all the time, might be related to wind conditions
- crappy boost below 2000km, and then a kick around 2200rpm
- sometimes city traffic is a pain. feels like I'm pulling a 2 ton boat... pulling away from traffic lights can be an exercise in patience, other times its ok.
- no CEL's
- no black smoke with the turbo lag.
- still have decent passing power in 5th gear passing cars going 110kph.
- getting about 5.3L/100km fuel economy, mostly hiway driving, not babying it.


I'm inclined to check the EGR cooler and see if there is a leak where the rod from the EGR valve enters the cooler. I've got an oil change due soon and will inspect. This mainly because I've noticed a hint of exhaust smell in the cabin at stoplights, other times, there is no exhaust smell....

Joys of driving a 10 yr old car.....

Most likely is a failed EGR cooler. I'd look there first.

I've been away on holidays and haven't had time to put the car up on the lift yet.

Strange, the car seems to be running great since I got home from vacation.... Good turbo response etc.

Found out that my ac is acting up. Cold air when moving, but it quickly warms up if stuck in traffic. Looks like something with the fans... Quite a few good diy out there. Will check fuse and fans...

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Turn the AC on and see if both fans are spinning. It is common for the armature brushes to get stuck in their guides such that they do not make contact with the armature correctly. This can sometimes be fixed by tapping the motor housing with something like a small hammer.

sptsailing said:

Turn the AC on and see if both fans are spinning. It is common for the armature brushes to get stuck in their guides such that they do not make contact with the armature correctly. This can sometimes be fixed by tapping the motor housing with something like a small hammer.

Click to expand...

The driver side Ac fan started turning after tapping it lightly with a small hammer and Ac on. Passenger side fan still AWOL.

I did the jb weld fix on the egr cooler. Hopefully the repair lasts.

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I was able to iron out the lumpy idle while stopped to be a faulty fuel temp sender, located just to the right of the oil filter on the front of the engine (vag-com verified it was reading 0-saturated that coincided with the lumpiness). Disconnected the electrical from it and it ran smooth as butter until I was able to replace it for a few bucks.

Mine seems to be lumpy at stop lights more often than not, especially when the car is up to operating temperature.

I have been able to get rid of it the last couple of times by putting the car in 1st and slightly engaging the clutch and then disengaging it. I wonder if it might be a failing dual mass flywheel?

When I feel better I'll look for the fuel temperature sensor on my vcds. Right now out with a wonky back.

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petee_c said:

Mine seems to be lumpy at stop lights more often than not, especially when the car is up to operating temperature.

I have been able to get rid of it the last couple of times by putting the car in 1st and slightly engaging the clutch and then disengaging it. I wonder if it might be a failing dual mass flywheel?

When I feel better I'll look for the fuel temperature sensor on my vcds. Right now out with a wonky back.

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Click to expand...

It's definitely the failing DMF. Just had the exact same symptoms, swapped it for an SMF all good!

I'm going to try turning on load via the alternator and Ac compressor 1st to check if it's the dmf or the fuel temperature sensor the next time it happens.....

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I would check the cam shaft. I replaced mine a few weeks ago. Prior to replacing I'd get a "lumpy" idle as you describe and it was going into limp mode, which sounds like what you are experiencing, though I had a CEL for turbo overboost and MAF. You are within the typical range for camshaft failure.

It was about 10c/50F ambient temperature and I had to take my daughter to her game. It's about a 60 mile round trip to the away arena.

I could faintly detect the lumpy idle at the occasional stoplight, and it would go away as I put more electrical load on the engine.... Both heated seats, fans on 4,rear defrost on.

I wonder if it happens more when the air temperature is warmer?

I'm going to do some further diagnostics on the fuel temperature doohicky.

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petee_c said:

It was about 10c/50F ambient temperature and I had to take my daughter to her game. It's about a 60 mile round trip to the away arena.

I could faintly detect the lumpy idle at the occasional stoplight, and it would go away as I put more electrical load on the engine.... Both heated seats, fans on 4,rear defrost on.

I wonder if it happens more when the air temperature is warmer?

I'm going to do some further diagnostics on the fuel temperature doohicky.

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Click to expand...

Again, same exact issue for me.... DMF DMF DMF... Its slipping out of line when it wants to- eventually it will break drastically

I can smooth out the idle with just turning on the rear defrost when I detect it at a stoplight.

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As far as I can tell, my fuel sensor checks out.... Fuel temperature is mirroring coolant temp within a degree or 2.

Dmf and camshaft are next on the items to check

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