Friend with TDI loosing power over 3000 rpm

[kuhli]

I've a friend with a 2003 VW Jetta 1.9 TDI that's loosing power at higher rpms, in the lower gears its around 3000 rpm, in fourth its down to 2500 rpm, fifth won't maintain 110 km/hr on an uphill. He's run VAG-Com and no codes pop up, he's changed the MAF on-spec and still no improvement. Also, when he first ran the VAG-Com he received an error (maybe 1056) that indicated a coolant temperature sensor had intermittent problems, it's been replaced with a green updated sensor.

When it's cold the VNT rod moves freely, so it doesn't appear to be sticking...no word on when it's hot...because its hot!

The car also surges when on cruise at highway speeds, when watching the VAG-COM the boost doesn't vary any more than it should. Under full throttle he's getting about 230 kpa of MAP that drops suddenly at the rpms listed at the top.

Anybody have any ideas? Turbo issues? N75 valve(would you get a code)?

[RobG]

Re: Friend with TDI loosing power over 3000 rpm

When was the intake last cleaned?

[Kor]

Re: Friend with TDI loosing power over 3000 rpm

Yes the intake and MAF should be cleaned, and I am not sure about the TDI but I am guessing oil can get into the intercooler as well.

[forkdork]

Re: Friend with TDI loosing power over 3000 rpm

check your MAF sensor, unplug it and see if the car runs any better...you will notice a huge difference at rpm's above 3k after unplugging if the MAF is bad.

[kuhli]

Re: Friend with TDI loosing power over 3000 rpm

A bit more info:

Car has 117,000 km on it.

The intake hasn't been cleaned, I presume you mean the intake manifold... What would the effect of a dirty intake be?

Second, the MAF has been replaced, could try running it unplugged though...

[B5]

Re: Friend with TDI loosing power over 3000 rpm

A bit more info:

Car has 117,000 km on it.

The intake hasn't been cleaned, I presume you mean the intake manifold... What would the effect of a dirty intake be?

Second, the MAF has been replaced, could try running it unplugged though...

Intake coked up. Get ready to fork out $500 out of your pocket or call Dave @ SFC for a fast and easy solution.

[kuhli]

Re: Friend with TDI loosing power over 3000 rpm

So you're saying the intake is full of crap, what would the crap be, EGR oil? Would this be warrantable?

Is Dave @ south centre the resident expert on this?

[B5]

Re: Friend with TDI loosing power over 3000 rpm

So you're saying the intake is full of crap, what would the crap be, EGR oil? Would this be warrantable?

Is Dave @ south centre the resident expert on this?

Intake full of crap? At that Km, I'll say absolutely has something blocking up the intake unless your friend did the CCV mod when the car was new.

Warranty? I don't know. Dealerships may very. (Look at NL POS clutchs incidents)

I'm sure Dave@SFC will be able to give you the solution. If you decided to see him then ask him to show you the EGR unit or an intake that has carbon carp build up.

[Stonewall]

Re: Friend with TDI loosing power over 3000 rpm

Intake coked up. Get ready to fork out $500 out of your pocket or call Dave @ SFC for a fast and easy solution.

Ohh stop being to negative, cleaning the intake is about a 3-4 hour job and needs less then $50 in parts. There are many write ups on the TDIclub on how to do it. Another thing to check since noone mentioned it but I bet it part of the problem is the snowscreen. Take the airbox out and then pull the nut off you see on the fender, pull that tube out and clean the screen. It is as simple as that.

[kuhli]

Re: Friend with TDI loosing power over 3000 rpm

Here's a dumb question...could this be a fuel pickup issue or fuel filter?

[Stonewall]

Re: Friend with TDI loosing power over 3000 rpm

Here's a dumb question...could this be a fuel pickup issue or fuel filter?

Possibly mot not likely. I would change the fuel filter every year or so anyways and so it wouldn't hurt to change it too. Check the screen first though then go spend money to try and fix it.

[kuhli]

Re: Friend with TDI loosing power over 3000 rpm

Ah...he forgot to mention that the fuel filter was changed when the problem began...

[Stampfan]

Re: Friend with TDI loosing power over 3000 rpm

99.9% of the time its an MAF petering out. Rip out the oiled filter (if its got one), try another new MAF, and give it another shot.

[B5]

Re: Friend with TDI loosing power over 3000 rpm

Ohh stop being to negative, cleaning the intake is about a 3-4 hour job and needs less then $50 in parts. There are many write ups on the TDIclub on how to do it. Another thing to check since noone mentioned it but I bet it part of the problem is the snowscreen. Take the airbox out and then pull the nut off you see on the fender, pull that tube out and clean the screen. It is as simple as that.

How simple? What do you mean by being –ve? Are you trying to lowball me on the cost? 1/10 of what I said $500~$50 bux. Gee. No one said you cannot DIY. If you like, you can squeeze all the pennies you want. I will not waste my time on that.

IMO I am pointing him to the right direction to solve the problem(s) by seeing the professional. He(Dave@SFC) is the professional and will not f-up the car. You aren’t and if he already knows someone, then he will not cry for help like that. Being said that you still can DIY, but once you open the hood and imagine you can do something. You will have nothing less than 99% f-up the car because you are not the professional.


Hay. Did VW tells the TDI buyers/owners that the intake will eventually coked-up and cost $ to clean or required to waste 3~4hrs of your life to clean? Awww………….

[Stonewall]

Re: Friend with TDI loosing power over 3000 rpm

Being said that you still can DIY, but once you open the hood and imagine you can do something. You will have nothing less than 99% f-up the car because you are not the professional.

Ohh I am soo sorry I totally forgot you can't remove 3 bolts
Maybe some people can and save themselves your $500, if it turns out it is not the problem then you have atleast crossed the free fixes off the list. Just because you are not able to work on your own car doesn't mean it takes a professional to fix it.