Turbo Troubles

[Noblescort]

I know I'm in danger of inviting some "try searching the forum" responses but here goes anyway.

Out in the car yesterday and all was fine for a while until I lost power. As has been described elsewhere, it "felt like driving a mondeo"

Rather than getting the stereo darth vader type sounds from the air filters, I get quiet spooling up noises and some very light waste sounds (sounds like it is coming from nearside air filter only - front turbo). At this point the boost gauge shows 0. If I apply more throttle, and hold it on steady, the boost gauge starts to oscillate up a point or two then retuns to 0. It does this 3 or 4 times a second with no added forward momentum.

Car is a 2.5 with standard turbos

I've checked all of the air hoses and they are all secure.

I'd like to check some other things but as this is my first turbo'd car I'm not really sure where to start. I've read a few comments about some of the potential causes eg blocked cats, faulty actuators, wastegates getting stuck open etc etc.

What should I check next?

[art411y]

defo actuators and wastegates 1st.i would have thought any turbo wear would show up as smoking exhausts?

[Noblescort]

The actuators are sprung and if faulty would close the wastegate and therefore create overboost rather than create no boost, wouldn't they?

As far as the wastegates themselves go, the symtons described in my earlier post would be evident if the wastegate were somehow being held open or jammed open?

Or have I got it all wrong? Any help appreciated.

[nonplussed]

This may not apply to your car, but how does your boost gauge measure the boost? I had these exact symptoms in a Saab 9000 Aero once - in that, the boost gauge isn't electronic, but literally measures boost somehow, which necessitates piping boosted air to the gauge. In my car, that (tiny) pipe came off, which created a leak in the system = no boost. Probably not what you've got but the symptoms were exactly that.

[Noblescort]

I assumed (perhaps wrongly) that the boost guage would be electronic. I'm sure someone cleverer than me will come along soon and enlighten me

[MrCredit]

Noblescort said:

I assumed (perhaps wrongly) that the boost guage would be electronic. I'm sure someone cleverer than me will come along soon and enlighten me

The boost gauge is mechanical.
There is a braided hose that runs from the plenum, under the engine, down the tunnel and up behind the centre console to the gauge.
Well it does on the GTO3 anyway.
Doesn't on mine anymore though.

[Noblescort]

Thanks for that. I wonder if the 2.5 is the same (I'm sure it will be. If you were Mr Noble developing improvements for the 3R, why would you go to mechanical if the 2.5 had electronic - you wouldn't, would you?)

Something else for me to go hunting for now

[Noblescort]

nonplussed said:

In my car, that (tiny) pipe came off, which created a leak in the system = no boost.

Wouldn't that also mean no boost guage though?

[jimbooo]

hi. I'm using my mobile to post this so can't link to other posts etc. I had exactly the same thing recently. Go back a few pages and look at the thread titled "lost 95% of power." thread. Or something like that. Good luck

Edited by jimbooo on Tuesday 12th May 22:48

[mgbond]

Noblescort said:

Thanks for that. I wonder if the 2.5 is the same (I'm sure it will be. If you were Mr Noble developing improvements for the 3R, why would you go to mechanical if the 2.5 had electronic - you wouldn't, would you?)

Something else for me to go hunting for now

The pipe in question on the 2.5 is on the top of the manifold just behind the inlet. its right in your face.

Bondy

[coolchris]

Hi my car had exact same symptons no power faint noise etc boost gauge still showing boost.Got my mechanic to give quick once over all pipes seemed fine then noticed that the large pipe that comes off the engine and goes to hard pipe that connects to intercooler had worked its way loose looked like it was connected but wasnt if you know what i mean.Pushed back on tightened up problem cured tooke car for spin and problem cured.

Cheers Chris

[Gadgeroonie]

where are you based ? i can take a look at it if you like

[The devil]

Hey Gadge, where are you, I am near St Albans

[Noblescort]

Thanks for the offer gadge, I'm in Southampton.

Any help would be greatly appreciated

[Gadgeroonie]

i'm in Hertfordshire - close to st Albans

NickyTwoHats and I often meet up for a Noble chat and a beer, fancy coming along

Southampton is a bit of a trek from here

[Noblescort]

You mean a chat and an orange juice of course!

Sounds like a good idea though, just need a car that works now, and I'll be there.

[sean_goodman]

Noblescort said:

Thanks for the offer gadge, I'm in Southampton.

Any help would be greatly appreciated

i am flying into southampton 2nd june and travelling down to bovington. stay until morning of 4th june.

if you havnt sorted out it by them i could pop by and have a look

[Noblescort]

And if I have, we could meet up for one of those orange juices in a pub somewhere

[Noblescort]

Who said wastegates....

This is what I found when I looked underneath at the front turbo



The E-clip's a gonna!!

[The devil]

Good stuff