I own a 2001 110bhp diesel Octavia. Sometimes whilst driving uphill or revving hardish (in all types of weather) the turbo goes to sleep but will wake up if the ignition is turned off and back on. A friend ran a diagnostic check which gave the error as 'turbo control pressure exceeded' but could not tell me anything else as his diagnostic software for diesels was limited. Can anyone shed any light on this?

maybe the actuator is jammed

It most certainly is the actuator pump on the turbo!

When this is sticking, the variable vanes in the turbo is not working and the ECU measures an overboost

I've experienced a similar issue on my chipped Oct VRS and never got to the bottom of it (as Kenneth Williams would say). Others have talked about a sensor on the crank...........? For me it ALWAYS happens going up steady inclines on half/three quarter throttle.

Is this likely to be the actuators?

Cheers for any feedback.

tim

Oct vRS, uses a different turbo thats operated in a totally different manner.

You really need to get the fault codes read as there are a number of causes.

Check out this thread.

Durchluftmessers again, IMHO!

http://www.briskoda.net/forums/octavia/oh-no-why-so-slow/64017/

different turbo on the 90 and 110 though mate.

Variable geometry on the 110, but same sensors? Perhaps not...

On my VRS it goes into full "limp mode" (as Larry Grayson would say) and after a quick knock into neutral, turn off, turn back on again is ok. No fault codes last time it was checked. Am having it serviced this week and they're going to plug it back in again..........

Thanks for your knowledge/opinions.

Almost certain it will be the vnt mechanism that is clogged up or stiff. It seems to be getting common on these now if you dont hoon the engine every now and again. It spools up ok but when the ecu tells it to back off as max boost is being reached the actuator is slow to respond because its stiff so it carries on boosting for a couple of seconds which then takes it over the max boost pressure and the engine goes into limp mode. If your pretty good with spanners you can strip it down and clean it. I think someone else on here has done this already with out to much bother and with good results too.

hope that helps

blimey!!!! DONT strip down a VNT turbo unless you are absolutely certain you can reassemble it afterwards...... there's a lot of little parts inside one of those little babies.....

I think the guy just separated it and cleaned the gunk out the vanes. It was pretty coked up in there too. like you said I would not recommend pulling one apart into little bits it looks a little compicated.

also you have to make sure when yoiu split the turbine shaft that you mark the positions so you can reassemble it the same otherwise it will be imballanced and it will kill itself...

I certainly don't think its the case of me not "hooning it" enough. However, I'll go out right now and give it some special loving and see if that has any effect...........