Turbo diesel - "turbo stuck on"

[NY]

I have a Peugeot 308 with a 1.6 HDi engine. It gave an "anti-pollution
failure" engine-management warning. The garage found that the turbo was
"stuck on" (the phrase they used when they returned the car to my wife while
I was out). I'm intrigued by what this means and whether it is harmful for
the car.

I presume the turbo spins continuously, driven by the exhaust, and any
excess inlet air pressure, over and above what the engine can take in (which
varies with engine revs and maybe accelerator position ie fuel injection
rate), is vented to the atmosphere via the waste gate. I presume a "stuck
turbo" means the waste gate isn't opening when required.

There was no change of performance in the car - from past experience (*) I
know what happens if the air supply hose from the turbo comes off when a
jubilee clip hasn't been tightened properly! - and the only indication was
the warning light.

The garage freed and lubricated "the turbo" (presumably waste gate rather
than turbine shaft) and couldn't reproduce the problem. A nice quick fix:
the car was at the garage for less than 2 hours from dropping it off to the
garage man delivering it back.



(*) A few years ago the car had been into the garage for some other fault
which had required the turbo-to-engine hose to be removed and later
refitted. Soon after I got the car back, it suddenly lost power going up a
gentle hill, and only just made it to the top. Driving home I couldn't get
the car above about 40 mph on the level, and on a long gentle climb (which
the car can normally do at 60) it struggled to get above 20 - very
embarrassing as a long queue of traffic built up behind me.

I booked the car in to the garage, not looking forward to the 30-mile
journey to get there, and then something made me check under the bonnet. The
air-inlet hose from the turbo to the inlet manifold was hanging off at the
turbo end. Once I'd tightened the jubilee clip (which fortunately was still
on the hose and hadn't dropped off), the car worked perfectly. I cancelled
the trip to the garage and let their service manager know that there was a
slight quality-control problem with checking that they had retightened parts
that had been removed.

[Brian Gaff (Sofa)]

I am actually almost sure that Jubilee clips wherever they can be found come
complete with a little fairy who loosens them over a few months untill they
drop off. Seen it on water butts and hose reels.
Brian

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[NY]

"Brian Gaff (Sofa)" <bri...@blueyonder.co.uk> wrote in message
news:s7o1mn$h85$1...@dont-email.me...

> I am actually almost sure that Jubilee clips wherever they can be found
> come complete with a little fairy who loosens them over a few months
> untill they drop off. Seen it on water butts and hose reels.

The Jubilee Fairy. Yes, I believe in her even more than I do in Santa Claus.


I did once have problems with a hose for something (I forget the details)
which refused to tighten onto shaft so it wouldn't pull straight off. No
matter how hard I tightened the jubilee clip, the hose pulled off. And I
confirmed that with the hose loose (ie not on its shaft) the clip could be
tightened much further, compressing the hose more, so it wasn't just that
I'd reached the end of the jubilee clip's adjustment. I found that rubbing
the shaft with sandpaper to roughen it solved the problem.