Rev's to 4k @ 55mph, supdders. will not go faster

[Nicker]

Ok this is yet another battle with my affordable ‘daily driver’.
Purchased a 91tsi AWD last month for a daily driver until winter is over.
Car has 102k miles on it and since then I’ve put 4new tires on, fuel filter, air filter, plugs, wires, exhaust manifold, oil/filter, all belts and the wonderful ISC. A basic tune-up to get ready for the winter.

Now my current problem is that the car is acting like its on 3cylinders. When coming home with the car from a 200 mile drive, one of the plug wires burnt and when it ran on 3 cylinders the car did not go over 55/60 mph, rev’d really high to get to that point (4k+), and then would start sputtering/surging and would not go faster.

Since then I got new magnacore wires and everything was okay.
Now with the only problem is as pre-turbo exhaust leak from the manifold to the turbo exhaust housing. I am going to get this fixed as soon as the gasket comes in the mail, but I do not think this could be the reason why it is not going over 55mph.

I put a second pair of new plugs in thinking one could be fouled, and still same thing. Each cylinder is firing, I removed each plug wire when idling and hear the motor stumble, and removed the new plugs and saw carbon. So all cylinders are firing, and I am out of ideas of what could be wrong. Could this be a transmission problem, as the fluid is at the right level, still red, no black or brown ash in it.

Thanks for all help.

 

[Ultimatedsm]

DOes your car go over 4000 RPM in part throttle? Or is it only a problem at WOT? Do a boost leak test if you answered Yes for the first and No for the second question.

 

[Nicker]

Yes the coil pack is okay. I am trying to get the car to go past 55mph without wot, but the faster I want to go, it needs more gas, not wot, just part throttle. I have done a boost leak test, but I will do another one when im doing my manifold to turbo gasket. So as of now I do not think there is any boost leaks.

 

[Mist3r Spool]

Yes the coil pack is okay. I am trying to get the car to go past 55mph without wot, but the faster I want to go, it needs more gas, not wot, just part throttle. I have done a boost leak test, but I will do another one when im doing my manifold to turbo gasket. So as of now I do not think there is any boost leaks.

Ahhh, I had a similar issue-it was a leak in my IC piping. It was a small leak but it caused my car to buck like hell when I punched it. Check for leaks. I ran into the issue again when I installed my upgraded injectors, it would hit fuel cut if I boosted at all. I'm on the waiting list to have my car dyno-tuned, and have been playing around with the settings and it still bucks a little bit, anyway it could be a mixture issue.

 

[drifterdturbo]

is this an auto? cause if it is, another thing it might be is the tranny failsafe... they call it limp mode.... i had a similar issue but my car was like it was stuck in one gear!!! it will have a doggy acceleration but when it gets up to speed it will wrap real high rpms. u might want to get the tranny checked out to see whats up!!! onther thing to be careful of is when u go to get on it, u can not boost when u are in overdrive!!!! if u do it will cause u to burn out ## overdrive and that is just more money spent that could have been prevented!!! and dont wait to long to get this check out cause u will cause serious damage to ## motor... i know, thats what i did and now im paying for it and i got away from the auto and converted it over to a manual on the same car!!! in the process of finishing up as we speek!!!!

 

[Nicker]

Yes the car is an auto, after some speak of the tranny, I did more searching and found it might be my TCU.

So I am going to open it up and check it out for any leaks or burnt marks. If all checks out good I am going to try to reset it hoping the car will go back to normal.

If those two fail, its time to do more searching I guess.

 

[Nicker]

Just to keep people posted, or for anyone that will do searches for a problem like this later on, this is what I found.

Removed the TCU after having to pull out those two side panels by the right of the gas pedal, and same location on pass side (to unplug wires).

Opened up board and found a 47uf 50v electrolytic capacitor to have 'leaked' (electrolytic capacitors don’t leak actual fluid; it’s just the sealant on the capacitor that runs or melts off, messing up the board. Anyway I removed the old cap. and cleaned with board with some electronic solvent cleaner and a toothbrush, looks brand new.

Went to radio shack knowing they will not have what I need, so I used a 47uf 35volt capacitor for now. Going to test out tomorrow, same farads but less voltage should work. Off of eBay I got myself 25 electrolytic capacitors with 47uf 50v same temp. rating and they look the same exact as the stock one for less then 5USD$.

So for now I am going to test the 35volt cap. and see how it goes, and even if this was my problem.

 

[green_bread]

How did it work out? Were you stuck in limp mode before you did this? If so, did it fix the problem?

 

[Nicker]

Sorry, cleaning the board and replacing the cap. with the right uf and volts did not work. So as for now, im stuck using the switches to shift. Keeping my eye's out for a tcu, but they are rare.

 

[TazExtreme3]

Look at http://www.transmissioncontrolunits.com/, they have them for $369.95 plus $150.00 core

 

[green_bread]

Sorry, cleaning the board and replacing the cap. with the right uf and volts did not work. So as for now, im stuck using the switches to shift. Keeping my eye's out for a tcu, but they are rare.

hey, man! i sent you a PM, check it out!

ADAM