HELLO,

went for a long hard run on the motorway today, and at start of the journey everything was fine, then I noticed the car no longer picking up on boost.

it climbs from minus 0.6 to 0.5 and that's it. the car accelerates fine but the max boost is now 0.5 bar and stays 0.5bar when foot to floor.


before it used to peak at 1.4 bar max on full throttle, it no longer does that.

Does that mean the turbo has blown.

I have checked it on code reader and its not thrown up any fault codes.

Does this mean the Turbo has blown? or could it be something a little more obvious.

I do have a 3 port boost solenoid fitted, its approx 10 months old.

please advise. i know little about the Scooby, but appreciate all the advice given .

 

Split hose or pipe popped off?

 

hi, all pipes and hoses thoroughly checked. all ok and in their right place.

 

Most likely is that your boost solenoid is stuck shut or inoperative, 0.5 bar is STD wastegate pressure on factory turbos. You could try giving it a clean with carb cleaner and a little squirt of wd40.

Cheers Iain

 

Just taken it out on another run, seems to be ok now, the boost pressure is hitting 1.4bar again. strange, can't really explain the temporarily loss of boost pressure, really weird.

 

Maybe ECU has disabled boost control due to detonation ? Are you running good fuel ?

You say the car accelerates fine but if only making 0.5bar it would have significantly less accelaration than at 1.4bar

 

i would like to do this as a precautionary measure.

I have some carb cleaner, where would you squirt it, just on the body of the solenoid ?

 

That's defo tied into the boost solenoid, it's quite common, I would suggest giving it a clean as they are prone to getting gunned up with oil deposits from the engine breather system.

Cheers Iain

 

Used to have the same issue on my bug wrx from time to time, especially if on a motorway or generally taking it easy. Tried cleaning the boost solenoid but was still the same after. Found out if I stopped the engine then restarted it, it`d boost fine then, like it reset itself. Never threw any CEL either. Had it mapped 10000 miles ago, and been fine since.Try restarting it when it does it again and see if it`s boosting ok then.

 

thanks most helpful. but will one ever know why this happens ? I was thinking more down to quality of the 3 port solenoid, as their are quite a few after market ones available, but I don't know which are the good ones out there.

 

That happened to mine sporadically for a couple of years, with a restart sorting things, but then it stuck in slow mode. Turns out the ECU was retarding ignition, probably due to false det, and an ECU reset restored things permanently. (Touch wood)

 

Perrin EBC pro is a good one. Small discreet an easy to fit. You may need to get a map tweak just after tho. But don't quote me on that