[Bart3298]

I just bought this Jetta and have have an issue with it. Sometimes when I am starting out in first gear it acts like it is loading up. I put the pedal all the way down and it just won,t take off. Sometimes when it does go, it puffs a big cloud of black smoke and then runs fine. This is something that happens once in a while (usually once or twice on my 25 mile drive to work or back). I have changed the fuel filter and when I did that I filled the canister with Sea Foam to clean the pump/injectors etc. This didn't help the problem. The car has 161,000 miles on it. What do I start looking for next?

Thanks!!!!

 

[Two Mikes]

This is just a guess: bad MAf or stuck turbo. Do you have a vag com?

 

[Bart3298]

No, what is a vag com?

 

[chittychittybangbang]

Vag com is the old name for the ross tech VCDS. It's a computer cable and software that lets you talk to the car's computer. There are a few things you can do without it but advanced troubleshooting requires it.

What recent maintenance has the car had? Other than the fuel filter?

There are a number of issue the car could have. Take it to autozone and first see what error codes show up. It's free and it will help narrow it down instead of wild guessing.

There are lots of things that could cause low power on your TDI. Some more common ones are bad MAF, stuck turbo, broken vacuum lines, bad electric fuel pump in the fuel tank, and more. It could also be intake manifold clogging. The car isn't getting air or fuel - you have to now figure out what it's not getting and why. Read this link and go through all the troubleshooting steps to narrow it down.

http://www.myturbodiesel.com/1000q_how_to/multi/lowpowerfix.htm

 

[Bart3298]

I can't tell you what prior maintenance has been done because I just bought it. Here's what I have done. Changed oil/filter, fuel filter, air filter, ran two cans of Sea Foam through 2 tanks of fuel, and just added some Racor Biocide to clean tank and fuel system on the fill I just did yesterday. I do have a code reader ordered from ECS Tuning and all the parts coming from them to change the timing belt since I can't find any records of it being done. When I start the timing belt job I will check the turbo and all the vacuum hoses.

Thanks for your help:thumbsup

 

[chittychittybangbang]

FYI the code reader from ecstuning that says they don't offer support for is the same as the cheap ebay cables. They don't offer support because it uses an old version of the VCDS software. You should be fine for basic use but it doesn't have the newer functions. I recommend a genuine Ross tech cable since it's specific for VW/Audi and only depreciates about $50 if you sell it used because the software license follows the cable.

 

[Two Mikes]

Autozone and the like also do code scanning for free.

 

[Bart3298]

So how much money are we talking for the Ross Tech cable? Where would I buy it? Thanks!!!!

 

[Two Mikes]

http://www.ross-tech.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=VAGCOM If your car has the oval headlights and is a mk5, the current body style, you need the Hex CAN BUS cable. If your car is an older square headlight mk4 Jetta, you don't.

 

[Bart3298]

VCDS Cable

I got a cable and a laptop and checked for codes. There are no codes in the system. How do I check the MAF specified and actual values to see if MAF is ok. I used the article on here but I can't get the same screens to come up to get the specified against the actual like the picture shows. It says th A5 will be different but I couldn't figure it out. Thanks!!!

 

[grizzly]

Go to engine ->advanced measuring blocks. Then check the boxes you want to view.

 

[orttauq]

I can tell you exactly what it is. Had the SAME exact issue with an 05.5 jetta TDi my mom purchased recently.

It's the wastegate actuator located right behind the cylinder head almost dead center. The actuator sticks, and causes the ASV to stick and block exhaust flow from spooling the turbine. You get the sensation of NO acceleration and a plume of black smoke from the exhaust, then all the sudden it pops and the car takes off. Do this...

Take the vacuum line off of that wastegate actuator. Get a can of lubricant (WD40 for example). Spray it into the actuator. Hook up some sort of vacuum device and put the actuator under vacuum. Watch the actuator rod move back and forth till it starts moving free and smooth. Put the vacuum line back on and take it for a good ride. It's been maybe 1k miles since I've done this and she hasn't been able to duplicate the problem. She knew exactly when it would do it in whatever situation, and it refuses to happen again.

VW's remedy is to replace the turbo, as this actuator is part of the wastegate which is part of the turbo, which no single part can be purchased separately. I've talked to a couple of TDI parts companies and idparts.com told me within a year he should have a replaceable wastegate actuator for the factory turbos. He's the one who told me to try this method and so far so good!:nana2:

 

[Bart3298]

I can tell you exactly what it is. Had the SAME exact issue with an 05.5 jetta TDi my mom purchased recently.

It's the wastegate actuator located right behind the cylinder head almost dead center. The actuator sticks, and causes the ASV to stick and block exhaust flow from spooling the turbine. You get the sensation of NO acceleration and a plume of black smoke from the exhaust, then all the sudden it pops and the car takes off. Do this...

Take the vacuum line off of that wastegate actuator. Get a can of lubricant (WD40 for example). Spray it into the actuator. Hook up some sort of vacuum device and put the actuator under vacuum. Watch the actuator rod move back and forth till it starts moving free and smooth. Put the vacuum line back on and take it for a good ride. It's been maybe 1k miles since I've done this and she hasn't been able to duplicate the problem. She knew exactly when it would do it in whatever situation, and it refuses to happen again.

VW's remedy is to replace the turbo, as this actuator is part of the wastegate which is part of the turbo, which no single part can be purchased separately. I've talked to a couple of TDI parts companies and idparts.com told me within a year he should have a replaceable wastegate actuator for the factory turbos. He's the one who told me to try this method and so far so good!:nana2:

Hey, thanks for the info. I cleaned the outside linkage at the actuator but never thought about spraying inside. I will definitely try that!!!! Thanks again!!!!!!!!!!!!!!!!!!!!!