Turbo Failure Mid Journey

[davyrob32]

When I was driving on the motorway I suddenly lost power whilst crusing along at 70mph. The engine still revved out if i dropped gears and the engine didn't cut out but I had no power or turbo to be exact. This has only happened a few times now but I dont want it to lead to something more serious. Do you know what could be doing this?

[Ravens]

If your turbo lets go, no power and lots of smoke and tears. Get it checked if you are sure it is the Turbo.

[davyrob32]

I'm not sure its the turbo, there's no smoke. Someone has mentioned it could be an air flow metre?

[gbrad2x]

It sounds to me like your clutch is slipping. Accelerate to 30mph(50kmph)andput the car in 5th. Now floor it. Does the engine labor or do you get the sudden rise in revs with no power that you were talking about?(clutch slip)

If does slip dont hesitate in getting it swapped. The DMF may also be damaged due to slippage as you metioned this has happened a few times now....

[sgtbanjo]

Sounds like limp mode to me, turbo cuts out to save itself or your engine from damage. There should be a fault code stored. You'll need it scanning and the problem rectifying.

My old TDI used to do it if I adjusted the tuning box to give too much power. It was fine up to 80 mph then limp mode until you turned off the engine and started it up again.

[davyrob32]

Na, its definitly not the clutch. This has happened only twice over a 4 week period and has cleared once the engine has been turned off and on again.

[Teflon]

If it a limp mode problem it's either the MAF, the MAP sensor or any one of half a dozen other possibilites up to and including a sticky VNT mechanism inside the turbo itself. As sgtbanjo says, get a fault code scan done. To my knowledge, the only problem that doesn't show a fault code is a faulty MAF, which is only going to cost you about £50 to swap.

Watch out for the next time it happens. Odds are that it will be when you increase the load on the engine but with a reasonably constant throttle position, for example when climbing a gradient on the motorway. The power just fades away and you find yourself going slower the harder you push the pedal.

Any chance that you have 40k-80k of gentle, mainly motorway miles on the clock? If so, there's a good chance it is a sticking VNT. Easy to fix if you don't mind taking the turbo off and stripping it down for a clean.

[davyrob32]

Cheers Teflon.

Yeah I do about 350 motorway miles a week and have clock ed 27k since I got the car 18months ago. Excuse my stupidity, what's a MAF & VNT.

[sgtbanjo]

MAF = Mass Air Flow meter, senses the amount and temperature of air entering the engine. These can get caked up and measure incorrectly.

VNT = Variable Nozzle Turbine(Turbo), A technology which can vary the amount of boost produced by varying the nozzles within a turbo. These can get caked up and not open or close properly.

[davyrob32]

Cheers banjo, I'll get it stuck on the computer and check it out.