Heres a quick rundown/history of the car.
Its a 2005, BEW. 149 xxx KM on it. It had a failing turbo/limp mode problem for about a year, I finally decided to do something about it and fix it. A friend of mine who is a mechanic had a similar problem with a VW that came into his shop, he did a Tbelt/waterpump, headgasket, and replaced the turbo assembly as well as cleaned the intake/intercooler etc.
We did a timing belt/waterpump on my 2005, we just simply untensioned the tensioner, slipped the old belt off and slipped the new one on being careful not to move either the crank or cam. We also pulled the intake and cleaned it, it was very very dirty. Also did the oil change, air filter, fuel filter, surpentine belt/tensioner.
Next we pulled the turbo, seperated it and noticed the vanes were very free, and moved fine. There was little carbon build up, however there was VERY excessive shaft play.
We put the car back together, it had more power, but the obvious wear on the turbo was causing a power loss. 3 weeks later the turbo failed, the shaft broke inside the center section somewhere. When this happend there was a very sudden loss in power, the car would only go 30km/h.
We got an updated VW turbo manifold assembly, replaced it and went for a roadtest. The car felt like it was still in limp mode, and all of a sudden I accelerated off a stop sign and the car 'took off' it had more power then I've ever felt in a diesel VW, regardless of throttle it kept accelerating. I hit the brakes hard (in gear), and shut it off around 4500rpm. The car didn't buck at this time, it just felt like the turbo wasn't working (still).
It appear's it sucked in some oil that had collected in the intercooler when the previous turbo failed, I guess it used this oil as some alternative fuel? Anyways. I removed/drained the intercooler and all charge piping and cleaned everything very well.
Now, I take it out for a road test, and it bucks very very very bad. Anything over maybe 10% throttle it almost feels like it hits a low rev limit, but happens earlier in 2nd then 1st. Depends on load it seems.
When I scan it I get a bad o2 in bank 1, (I think when the turbo failed a section of the exhaust wheel broke and took out the tip of the sensor), as well as coolant reading high sensor. The coolant code when away when scanned, it does come back (been around for a couple years), however the o2 won't clear.
The bucking is really horrible, the car is undriveable. It free rev's in neutral just fine, and starts/idles well. The car isn't smoking excessively either.
Im curious what I should check? I don't know where to go from here really. I wish I was getting some more codes when I scanned it so I would know what to look at. I've considered pulling the valvecover and inspecting the wiring on the injectors, and I also wanted to disable the EGR, somehow just keep that flapper shut. I don't care about the CEL. I really just want the car to run properly/reliably.
Also, is there any way to test the wiring going to the wastegate accuator? I read its a common spot for problems, with a visual inspection I don't see anything wrong. Could the timing belt have jumped a tooth during the rapid acceleration? Would being off a bit cause excessively bad bucking?
Any help would be great
Thanks!
Its a 2005, BEW. 149 xxx KM on it. It had a failing turbo/limp mode problem for about a year, I finally decided to do something about it and fix it. A friend of mine who is a mechanic had a similar problem with a VW that came into his shop, he did a Tbelt/waterpump, headgasket, and replaced the turbo assembly as well as cleaned the intake/intercooler etc.
We did a timing belt/waterpump on my 2005, we just simply untensioned the tensioner, slipped the old belt off and slipped the new one on being careful not to move either the crank or cam. We also pulled the intake and cleaned it, it was very very dirty. Also did the oil change, air filter, fuel filter, surpentine belt/tensioner.
Next we pulled the turbo, seperated it and noticed the vanes were very free, and moved fine. There was little carbon build up, however there was VERY excessive shaft play.
We put the car back together, it had more power, but the obvious wear on the turbo was causing a power loss. 3 weeks later the turbo failed, the shaft broke inside the center section somewhere. When this happend there was a very sudden loss in power, the car would only go 30km/h.
We got an updated VW turbo manifold assembly, replaced it and went for a roadtest. The car felt like it was still in limp mode, and all of a sudden I accelerated off a stop sign and the car 'took off' it had more power then I've ever felt in a diesel VW, regardless of throttle it kept accelerating. I hit the brakes hard (in gear), and shut it off around 4500rpm. The car didn't buck at this time, it just felt like the turbo wasn't working (still).
It appear's it sucked in some oil that had collected in the intercooler when the previous turbo failed, I guess it used this oil as some alternative fuel? Anyways. I removed/drained the intercooler and all charge piping and cleaned everything very well.
Now, I take it out for a road test, and it bucks very very very bad. Anything over maybe 10% throttle it almost feels like it hits a low rev limit, but happens earlier in 2nd then 1st. Depends on load it seems.
When I scan it I get a bad o2 in bank 1, (I think when the turbo failed a section of the exhaust wheel broke and took out the tip of the sensor), as well as coolant reading high sensor. The coolant code when away when scanned, it does come back (been around for a couple years), however the o2 won't clear.
The bucking is really horrible, the car is undriveable. It free rev's in neutral just fine, and starts/idles well. The car isn't smoking excessively either.
Im curious what I should check? I don't know where to go from here really. I wish I was getting some more codes when I scanned it so I would know what to look at. I've considered pulling the valvecover and inspecting the wiring on the injectors, and I also wanted to disable the EGR, somehow just keep that flapper shut. I don't care about the CEL. I really just want the car to run properly/reliably.
Also, is there any way to test the wiring going to the wastegate accuator? I read its a common spot for problems, with a visual inspection I don't see anything wrong. Could the timing belt have jumped a tooth during the rapid acceleration? Would being off a bit cause excessively bad bucking?
Any help would be great