Afew issues with my 150

[tungmeister]

Hey guys, not really sure if these are major problems but figured I'd list everything and see what people think, It's my first time with a VAG car and a modern diesel so I'm somewhat lacking on knowledge of these cars. On a cold start there's always some white smoke produced from the exhaust and the idle is abit lumpy/clunky until the engine has been running for afew minutes then it's perfectly smooth. Under acceleration the car seems to vibrate more so than it should, I've had the car 6 months now and this hasn't changed in anyway, in my friends 115 there's not really any vibrations which it what I'm basing it against. On odd occasions there'll be random flat spots under heavy acceleration, I've already checked all the boost pipework and everything seems in order. I've logged boost reading in vcds in the past and not seen any problems but It seems totally random when a flat spot will appear so I've been unable to log when it has occurred. That's about it, tell me what you think!

Edit: forgot to mention there's also a bit of a judder when you turn the engine off, this seems to be much more pronounced just after the battery has been disconnected but seems to decrease over time?

[Rhyso]

Have you logged the MAF readings?

Also what mileage is the car on?  Anything approaching 100K could be running into camshaft problems....

Injector loom can also break down causing intermittent power

[tungmeister]

Car's done 137K and I've put about 3-4K on it since I bought it. I did think about the cam but the engine sounds perfect when its running (other than a noisy aux tensioner). I logged the MAF a while back and everything seemed fine (was matching requested). all the things I've mentioned haven't changed At all over the period hence why I've not done anything about it. I'm suddenly feeling like I want to work on the car so thought I'd find out what's what.

[Rhyso]

Vibration could be a number of things from a failing DMF to worn suspension components 

Do you know what has been replaced on the car??

Without sitting in the car myself it can be a little hard to pin down the exact problem 

[tungmeister]

I know, That's the problem, I need someone local who has lots of experience with these to diagnose what's wrong with it. I've plenty of mechanical capability but since I've no experience with these I can't diagnose it. I did think about the DMF but the clutch feels fine and there's no vibration through it just a general sort of "VRRRRRRR" as I accelerate. The other thing that's been putting me off fixing her up is the fact that it's got after market locking nuts that I don't have a key for which is annoying.

[scarr89]

I had a flat spot which lead to clean my MAF which sorted out that problem. My 150 is quite rattly but that maybe because I have a stiffer engine mount

My car on start up always smokes. I have recently learnt that diesels will run 'lumpy' if it is cold but will then tick over as normal.

Hope you get it sorted!

[tungmeister]

Ye, I've heard that it's pretty common for the 150's to be abit lumpy and smoky on startup once they've afew miles under their belt so I'm not really worried about that, figured I'd mention everything though. Regarding the shudder on shutdown I've already had my anti shudder valve off and given it a good clean so it's working 100% so shouldn't be related.

[scarr89]

Do you have the hoses going to and from the ASV are they blocked? Or broken, or split? Check all your vacuum hoses perhaps? I don't have an ASV as I removed my EGR and it is a little clunkier on shut down because of that...

[tungmeister]

The anti shudder valve is fine, I've checked all the vac system by running through the engines output test with vag com, everything is working at it should. It basically does this on shutdown http://www.youtube.com/watch?v=jXJ6YvV90BU though it's not as severe.

[jonno72]

hi, long time lurker, none poster here ,  my 150 smokes and is lumpy on first start up too, but only after it has stood at least a few hours, after that it starts up fine.
I had a mondeo diesel before the VW and when they start to do this on start up it is normally related to an injector problem but i'm not sure about the VW's.
Also when i got my golf it had the random hesitation under power issue you mentioned and after thorough checks i could'nt cure it, until i removed my EGR valve, cleaned out my inlet manifold and fitted an allard EGR replacement pipe and all is fine now, hesitation has totally disapeared, hope this is of use.