5 replies to this topic

[dinelli]

My MK3 ST is kicking out a bunch of light grey smoke when I start it up after a day or so of inaction.

And then will come out in smaller amounts when I change gear.

I have lost some power - noticeably when I change up a gear a little too early.

I can floor the accelerator after the gear change and the power just isn't there (similar to limp mode for a few seconds, but without the warning light) If I ease off and change down again I can gently coax up to the speed I want gradually - going easier on the accelerator, then up with the gear again, and then all is good. Although that slowness normally angers whoever is behind me!

The car will happily pootle down the motorway at a decent speed without issue, and I'm doing two 80-mile journeys each week.

It's a 56-plate deisel ST, 140k miles.

 

I changed the EGR valve myself about 18 months ago, and about a year ago the boost pipe that comes out the bottom of it split so I changed that myself too. (I dont have ramps so I changed the pipe from above instead of going underneath. not easy!)

The difference in performance the boostpipe change made was phenomenal. A massive cloud of soot came out the back the first time I took it out and from that point on it drove like an absolute dream.

Although a year on, that change has faded and now I'm getting the loss of power coinciding with the grey smoke.

 

I put a bottle of Wynns diesel system cleaner through a few weeks ago, and it felt slightly more capable for a while, but it didn't make any difference.

 

I was wondering if the turbo was on its way out, although with the bonnet up I can see the actuator popping up nicely with each press of the accelerator.

 

Last weekend I checked that the boost pipe I replaced is connected properly at each end and also had a look in the top of the EGR, but didn't see anything worthy of note. What I did notice was the that when I took the top jubilee clip off the boost pipe at the EGR end, the pipe was fused onto the EGR valve. It just wouldn't shift. That's perhaps not a problem but strange all the same. Maybe that'll teach me for buying a pipe on ebay.

 

So I've got two questions..

 

1) Has anyone had these grey-smoke-and-loss-of-power symptoms before and might like to suggest what could be causing it?

 

2) I'm tempted to try the turbo drill-and-tap with the mister-muscle-with-a-straw thing that the northern bloke on youtube does, but i've heard its not an easy job, so as a relative novice in car mechanic stuff, I'm looking for a youtube style walkthrough for the drill-and-tap task - like I had walkthroughs for the EGR and boostpipe changes. So second question - does anyone know of a good drill-and-tap video to show how that's done?

 

I'm thinking I'll have to drop it in to a garage soon because I'm worried it might fail completely while I'm half way down the motorway.

Although I would prefer to sort the problem myself and save some cash on garage labour and parts markup.

 

Many thanks in advance for any advice/tips,

 

D.

 

[nicam49]

Also go on youtube and type in search box 'Mr muscle turbo fix'

Try a cheap leakoff test of the injectors for starters.

[ST56]

Hi

 

Try unplugging the electrical connector from the EGR this should isolate the unit and check if it has developed a fault.

 

Peter

[hardy1812]

Have you checked all intercooler hoses ?? any whooshing type noises??,,,I too had/have a similar issue were sometimes mine feels like it has no power,
I use millers eco max diesel for the white smoke on start up and seems to help with less smoke
I too have changed lower egr pipe due to small split but I completely deleted the EGR and cooler pipe,,,(but mines a EURO 3 engine so no light to worry about) and the opposite side of the intercooler is prone to failing,,, check all intercooler pipes and especially the jubilee clips as this pipes intercooler side one had corroded and the hose popped off and gave me no power at all,,,, and no management came on...,
Also check the intake pipe from the air box to turbo these can split next to the turbo, not sure if this would give the issue but worth a look,,,,

[dinelli]

Also go on youtube and type in search box 'Mr muscle turbo fix'

Try a cheap leakoff test of the injectors for starters.

 

This is the video I mentioned in my original post. I was looking for something step by step that I could follow.

Cant find anything of that sort.

 

Although I did a quick google on the mister muscle turbo fix as suggested and found this on a VW forum.

Suddenly the idea doesn't sound quite so appealing!

 

https://uk-mkivs.net...le-turbo-clean/

[Mondygeek]

https://youtu.be/SFDMd8eVVXo
Also go on youtube and type in search box 'Mr muscle turbo fix'

Try a cheap leakoff test of the injectors for starters.

This is the video I mentioned in my original post. I was looking for something step by step that I could follow.
Cant find anything of that sort.

Although I did a quick google on the mister muscle turbo fix as suggested and found this on a VW forum.
Suddenly the idea doesn't sound quite so appealing!

https://uk-mkivs.net...le-turbo-clean/

I'm assuming you did not read the whole thread, the problem was not Mr muscle it was caused by a hole in the exhaust flexi

Edited by Mondygeek, 16 September 2020 - 08:26 AM.