Black Smoke And Judder Under Load

[davgree]

Hi, my Galaxy (2004 115 Tdi Auto Engine Code AUY1; with 130k on the clock) has developed the following symptoms:

 

Slight loss of power under load in the higher gears (40 mph+), with a fair amount of black smoke, a bit of a misfire sound (like its not quite running on all 4 cylinders) and some real heavy juddering, but the juddering is only under the highest of engine torque load.

 

In neutral, if you rev the engine you would think nothing is wrong, no misfire sound or judder and black smoke only when the revs hit about 4000rpm, gentle driving around town would also lead you to think the car was fine.

 

I have VAG com which shows no fault codes except the odd over boost, which I am use to and lived with for 18 months+

 

I have replaced air filter, MAF and now the CAT, which has not cured the problems, if anything, it smoked more after changing the MAF!

 

Recently, since above problem started, now when cold or not driven for 30 mins plus, the car acts like it is in limp home mode for about 30 seconds, then the power turns back on over about a 5 second period and is then fine (apart from above symptoms) until left again for 30 mins or so! - No restart needed like when it over boosts. This symptom seems to get worse by the day!

 

Anyone had this or a similar problem?

 

Advice welcomed :wacko:

 

Thanks, Dave.

[galaxytdi115]

It`s just that as tdi`s get old they need to get to normal operating temp b 4 they can work properly underload,i thought me cam belt had snapped at first after i set off enthusiastically and limped for about 500 yds then it wheelspan and shot off like a rocket.

[insider]

Check the fuel system. When was the fuel filter last changed?

Under load the engine demands more fuel, if it's not getting it then you will lose power.

[davgree]

It`s just that as tdi`s get old they need to get to normal operating temp b 4 they can work properly underload,i thought me cam belt had snapped at first after i set off enthusiastically and limped for about 500 yds then it wheelspan and shot off like a rocket.

 

After leaving for 20-30 mins the engine (water) temp is still around 90 degrees, so i dont think its a 'cold' issue, sure it is something else, just dont know what!

 

Also getting a whipping noise at this point, i thought it sounded like a belt whipping but have found the noise is in the airbox when you let the power off, this noise is becoming more frequent and more so after car has been left to stand for 20-30 mins.

[davgree]

Check the fuel system. When was the fuel filter last changed?

Under load the engine demands more fuel, if it's not getting it then you will lose power.

 

New fuel filter has been fitted, with no difference.

I think black smoke is un-burnt diesel, so that should rule out lack of diesel.

 

 

Had new exhaust recycle valve fitted last week, it was very blocked with wet carbon and oil, the pipe from the exhaust was 100% blocked. I now have a bit more power, but still black smoke and spluttering when engine under load and car will go into limp home mode far more often than before new EGR fitted- vag com error now shows the famous 'boost control positive deviation' error message! - This happens far more when car is just under normal temp.

 

Local garage now suggest new turbo as variable vains maybe past sell by date- carbon damage, anyone been in this situation?

 

Thanks,

 

Dave.

 

ps. Free VAG Com Check (Full version) for anyone who wants to drive to Gloucester! Text me on 0794 114 0518

[NikpV]

have a look here - link was on external links page in faq

[davgree]

have a look here - link was on external links page in faq

 

Thanks for the link NikpV, thats been a real help, turbo is coming off on Tuesday, will post the results... Thanks again!

[CM2007]

My initial thought is possible turbo, either wastegate not operating properly or as you said, veins might be knackered.

I work in a commercial dealer and if ever we get black smoke and loss of power issues, a lot of the time it's turbo.

 

Hope you get it sorted.

 

Mike

[davgree]

New turbo now fitted (new Garrett not recon), bad news as it has not sorted the black smoke and loss of power with judder and misfire problem. On the up side, it has cured the limp home mode problem and the lack of power (like it was in limp home mode) when cold or left to stand for 20 - 30 mins.

 

Got my new Garrett turbo from http://www.originalturbosdirectltd.co.uk/ -Very Good service and the price was right!

 

Under half the price of The Fraud Main stealer and it was an original part. The old one that came off was Garrett, so it is not a WV made part.

 

The old turbo was at the end of its life, jamming when spun by hand and the variable vain system was very limited in movement and sticking.

 

 

 

Anyone got and ideas for this problem now then please: Black smoke and loss of power with judder and mis-fire under load, but fine at low revs and low power demand. Fuel consumption is down about 50-70 miles per tank. Also if stationary and in park, hold engine at a constant 3000rpm, it will emit white smoke that stinks of un burnt diesel, just like the booster heaters do sometimes!

[seatkid]

Sounds as if you have clogged up injectoritis.

 

Bang in a double or even triple dose of Millers Diesel Power Sport 4 into the tank. Then take it for a session of Italian tune ups (full revs in 3rd gear). Watch out for the poor guy behind you who will be cursing you with the smoke and soot coming out and blinding him. You should repeat this a few times probably over 2 -3 days until the black smoke is much reduced.

Edited November 20, 2008 by seatkid

[Scorpiorefugee]

Yup! I think that's what fixed mine, except I used the 'Oh dear, I've just put a few litres of unleaded in. &0 Edited November 20, 2008 by Scorpiorefugee

[davgree]

Thanks Seatkid and Scorpiorefugee, will give the Millers Diesel Power Sport 4 a try, followed by a touch of unleaded and see what happens.

 

If that fails, do you think injectors out and sent for testing at http://www.dtmfuel.co.uk/ is worth while? Spent quite a bit now on parts, past the point of no return! - Car has covered 135k, how long should injectors last these days?? :blink:

Edited November 20, 2008 by davgree

[seatkid]

I think injectors should last the lifetime of the vehicle. It depends on the quality of the fuel used, filtering and the nature of your driving. They do get gummed/sooted up however if you are a gentle driver leading to poor spray pattern and in extremes poor fuel metering and lack of atomisation (dribble). The fact that your EGR was blocked up, indicates the same is likely to be true of your injectors (and lots of carbon in the piston crown area and exhaust ports etc etc

 

The other possiblity is your PD engine may not have had the correct oil at some point, and the camshaft is badly worn, leading to poor injection. But try the millers first, remember it'll take quite a while to shift the gunge so don't expect an instant improvement.

 

IMPORTANT: Make sure your cambelt/tensioner is in good order (i.e. was changed within the last 40,000 miles) before you try the italian tuneups!! Also make sure the engine is warmed up before you start with the high revs.

[davgree]

Thanks Seatkid for the advice, I will give millers a go.

 

I talked to two different Diesel specialists today about PD injector problems, one told me he can send them off for testing at

[Scorpiorefugee]

Just a quick additional comment. My trick of adding unleaded was a genuine accident and I didn't use the "Italian tune up". My problem cleared over about half a tankful (400 miles) at gentle motorway cruising having been a problem for about 4k miles. My old tub has done 220k and is now running sweetly again. I think it started when I put some cheap Supermarket fuel in.

 

I would be nervous about adding unleaded to a more modern engine. Perhaps others who are better informed may comment on this.

 

P.S. Just had a quick re read and a silly thought. Have you checked the intercooler for blockage (Gunk).

 

I ran mine for a test with the pipe disconnected from the feed to the manifold. this does mean no filter or turbo but it did run and, in my case, proved the fault to be elsewhere. I also checked the manifold pressure tube to the ECU bu blowing down it and monitoring the read out on the VAG thingy.

 

Beyond this I can only offer sympathy mate.

Edited November 22, 2008 by Scorpiorefugee

[seatkid]

Safer to stick to Millers - guaranteed not to damage components - it has high lubricity and the cetane boost will make the engine sound a lot sweeter at idle. Its about Edited November 22, 2008 by seatkid

[davgree]

P.S. Just had a quick re read and a silly thought. Have you checked the intercooler for blockage (Gunk).

Beyond this I can only offer sympathy mate.

 

Thanks for that, have checked inter cooler, unfortunately there is no blockage there. Will give the Millers a few more miles yet, then try something else.

 

If anyone wants some Diesel Sport 4, if you reserve on line at Halfords and collect in store, you will get an extra 10% off... that will also save driving to the store and finding it's out of stock! :(