Richard Curtis

If its not the dump valve have a look under the turbo heatshield.

There should be small circlip holding the actuator arm to the turbo wastgate mechanism.

If this has come adrift it can sometimes give the symptoms you have - the arm does not engage properly and can jump in and out of position, when disconnected the wastegate arm flops to the position that by-passes all the boost.

Happenned to my legacy a few years ago and also seen an impreza with the same fault.

Rich

[Edited by Richard Curtis - 7/5/2003 11:40:33 PM]

LeonT

car will sometimes boost and other times it wont,

sometimes i can feel the turbo hesistating and then it will all off a sudden boost,????????????????

it is ok for a couple of mile then plays up again for another cple of mile,

MY00
group A downpipe,
blitz nur spect system,
ppp fitted,

itg panel filter,

please help me

many thanks leon

nom

Boost guage?
The thing to look out for if it's sometimes going & sometimes not is the boost it's going at when it doesn't appear to be boosting (sorry - not very clear there ) as it's possibly the ECU panicking. Hot weather (apparently) & all that.

Once the boost has dropped off, does it stay like that for a while/until the ignition is cycled, or is it random?

How's the idle? (when the engine's hot)

Delboy2

ECU going into safe mode?

LeonT

no boost gauge,

but yes it does it randomly,

even in cold weather,

what would make the ecu panick??

even when the boost not working. i can still hear the turbo whistling/spining,

thanks for the intrest

Delboy2

Is the car hitting overboost (Fuel cutting). This could cause the ECU to panic. Have you tried putting the ECU into diagnostic mode to see if there are any faults? If no it may be worth trying as the ECU might be seeing a sensor fault causing it to 'panic'.

LeonT

how do i put it into dianostic mode?

LeonT

yes sometimes it will over boost

very rair though

johnfelstead

are you doing a lot of steady speed driving in a que of trafic when you get this problem? say driving at 40MPHish with a constant throttle before flooring it to pass?

LeonT

no not at all,

it will do it even if i have been giving it stick for a while

johnfelstead

You may have a sticking dump valve that sometimes sticks open, letting the boost out.

LeonT

right ok,

ill have a look, that does sound like a good reason ,

ill take it off and try and free it, mant thanks

ill let you know how i get on