Smoke and sudden powerloss under load at speed??

[kaipassat]

Hi i recently bought a 98 B5 estate, with 1.9 tdi, enine number ahu419952, i am not sure how many h/p is supposed to have?

Any way it now has about 170k on the clock and was running fine and pulling up hills in 5th gear.

Now when at speed on the motorway the throttle dosnt respond as it did and if i put my foot down to over take there is a puff of black smoke from the exhaust. Also when going up hills on the motor way, it will suddenly lose power and start smoking badly. it dosnt slow down but i have to put my foot down further to maintain speed.

It seems to me that its chokeing or the turbo is sticking?

Any ideas, i am not a mechanic and dont have a manual, but have worked on many not-as -complicated cars before.

thanks

[martin1810]

It's going into limp mode and so not boosting. You need to get a vag-com read to give you a clue. It's often not the turbo but the vacuum pipes going to the turbo that causes this problem.

[cazyp]

As Martin said get fault codes read by vag.com. Either buy your own copy/lead - see the vagcom section of the forum, or get a garage to read the codes.

Most likely is turbo overboost caused by a split vacuum pipe, or intercooler hose. Second (on my list) is a faulty MAF sensor) but could be a sticky actuator/the EGR valve or turbo vanes stuck due to coked-up housing - although I would expect them to stick at their lowest RPM - not when they are spiining their heart out pushing an engine up a hill..

[kaipassat]

I just inspected what i think are the vacume hoses (looks like fuel line?)

There is a short section going into the something on top of the turbo, it feels a bit iffy, will change it tommorow and see what happens.

Thnaks for advise, not sure what the other three letter abreiveations you were talking about are?

thanks

[martin1810]

Blow into the pipe that you have found. If you can you have a vacuum leak. You might have to change all the hoses.

[cazyp]

MAF - mass airflow sensor - the big round thing on the end of the air filter box.
EGR exhaust gas recirc valve - the round shiny metal thing with a small hole in the side under the rubber 'cap' on the engine cover. HTH.

[kaipassat]

upon further investigation, under the engine cover, looking from the the front, at the top left side of the engine there is a plastic round thing with two tubes going in to it, the bottom of this part goes in to the engine.

One of the tubes is missing a clip and is lose, and the part that goes into the engine is cracked.
what does this bit do?
should it sealed?

could this be causeing oil to get in to the air system?

thanks

[cazyp]

Can you post a picture of what you mean please?

[lexa mac]

Try a new air mass meter. its the last thing before the tube work going down to the turbo. { Left hand front side of the engine compartment.} There is also another tube which comes up to the engine cover breather. These tubes need to be crack free. I have had this before and it cost me a fortune the first time finding out what was wrong. Many of the fault diagnostic computers seem not to be able to recognise the fault. They are on E-bay for £20 or so but get the correct one for the engine. The tubes are hard to come by even from VW as there are so many different ones and their sort codes and pictures are general and not specific.