I put 2 lots of Forte in the tank and all the while it was in there I didn't have any problems but a week later the problem has appeared again, is it worth putting 4 lots in? should I have put the advanced formula treatment in with it aswell?

I've tried the Mr Muscle a while back and that worked for a while!

Hi I had a couple of instances of sticky vane overboost limp mode both times going up the same hill near home with a cold engine. A combination of premium diesel every 3rd or 4th tank full and a bottle of archoil ar6400-D MAX has stopped it for 9 months and counting.

In my own experience (with Forte) turbo 'cleaners' added to fuel do not work. It was a waste of money. My car used to be plagued with sticky vane over/under boost problems. I eventually cured mine from doing this when I installed new guts in the turbo. I am not saying you need a new turbo but during the work I stripped down the VNT mechanism and cleaned it by hand then re-installed it. Surprisingly the mechanism was not too sooted up with carbon as I had feared. There was some carbon there but the main issue was with a golden varnish layer or residue all over everything from 150K miles. it was this layer that had to be removed to get the mechanism working freely again. The layer of crud was very difficult to remove on the bench, even with some very aggressive chemical solvents (alkaline Mr Muscle & brake cleaner xylene based sprays) used overnight and it ultimately required careful physical abrasion with some very fine emery cloth to remove it. I can see why in your case a Mr Muscle flush may help in the short term but it will only slacken things off temporarily before the gunge fights back and builds up again and causes sticking.

 

How many miles has your car done? Perhaps a professional service that can physically clean your turbo may be more effective, unless you are handy with the spanners and prepared to strip it down, clean and rebuild it yourself?

Oh, one other thing I forgot to mention. My car also had a small leak in the vacuum system that is used to actuate the VNT mechanism. Once that was sorted the turbo worked much better and consistently, with improved power. A vacuum leak can produce the same symptoms - perhaps something to get checked out too by a garage (i failed to spot it).

 

good luck.  

13 hours ago, Excision said:

In my own experience (with Forte) turbo 'cleaners' added to fuel do not work. It was a waste of money. My car used to be plagued with sticky vane over/under boost problems. I eventually cured mine from doing this when I installed new guts in the turbo. I am not saying you need a new turbo but during the work I stripped down the VNT mechanism and cleaned it by hand then re-installed it. Surprisingly the mechanism was not too sooted up with carbon as I had feared. There was some carbon there but the main issue was with a golden varnish layer or residue all over everything from 150K miles. it was this layer that had to be removed to get the mechanism working freely again. The layer of crud was very difficult to remove on the bench, even with some very aggressive chemical solvents (alkaline Mr Muscle & brake cleaner xylene based sprays) used overnight and it ultimately required careful physical abrasion with some very fine emery cloth to remove it. I can see why in your case a Mr Muscle flush may help in the short term but it will only slacken things off temporarily before the gunge fights back and builds up again and causes sticking.

 

How many miles has your car done? Perhaps a professional service that can physically clean your turbo may be more effective, unless you are handy with the spanners and prepared to strip it down, clean and rebuild it yourself?

Just over 125k, I  did initially take my car  into a garage with the problem but got told I needed a new turbo straight away!!! I dont really trust garages with telling them a  job that I want done EXAMPLE: cleaning the turbo. Because again they could tell me any old cobblers!!

Putting additives in the tank to clean the turbo relies on the cleaning agents to survive the combustion process and then do the job on the way out... I'm not saying the likes of Forte never ever work, but I think more direct applications of cleaning agents will see better results!!

 

I did the oven cleaner trick on my turbo after suffering overboost limp home mode a few times, 3 months later it's been fine ever since. I expect the problem will return, but I don't mind doing the job as part of the regular servicing.

Driving it hard and using the full rev range does help to keep things moving and soot free. High revs and a hard throttle get the turbo nice to hot to help burn off deposits. Though this is only likely to work when your issue has been solved.

 

I like to get on the M-Way when I have the chance and hold the revs around 3.5-3.8k for about 10 minutes to help getting things hot.

You're simply delaying the inevitable. Replace the turbo.

 

Do it now before it fails and either takes out the DPF or leaves you and family stranded at the side of the road.

well, whatever, easiest & permanent fix is a new turbo if it is indeed sticky vanes. The garage have given you the best option for both you and them.

I cant afford to pay for a new turbo which is why Im trying cheaper methods