Hi All

Hoping someone might be able to help with a query I have.

Whenever I turn the car off I get a rattle from somewhere inside the engine bay which lasts for no longer than a second, maybe two at the max. It sound like a marble being rattled in a tin can, it happens regardless of whether the clutch is in or out when I turn the car off, and it doesn't happen when I start the car. I think I have heard it in the past as I've pulled away on a couple of occasions, but only if clutch engages at very low revs, but not totally sure on this, and it definitely hasn't done it pulling away lately. 

Any views on this one would be greatly appreciated, and thanks in advance.

16 minutes ago, bigshorty said:

rattle from somewhere inside the engine bay which lasts for no longer than a second, maybe two at the max.

On shut down, the PCM (engine computer) will test certain items. On my 1.8, it tests the EGR, and this rattles, whines a bit (I can only hear this part from under the bonnet), and clunks. These tests can not be done at start (may be no time) or while running, so shut-down is best.

Try a shut down with the bonnet up, and the clip-on engine cover removed.

So hopefully it is quite normal.

Peter.

27 minutes ago, Tdci-Peter said:

Try a shut down with the bonnet up, and the clip-on engine cover removed.

Would this be to try and locate where the sound is actually coming from?

34 minutes ago, bigshorty said:

Would this be to try and locate where the sound is actually coming from?

Yup.

Cool, I'll give it a whirl when the rain gives up!

Thanks for the info.

Think I've located the rattle / clatter noise when turning engine off. To me it seems to be coming from the top left (drivers side) rear area of the engine (photo attached marking rough area where noise occurs, imagine engine cover isn't there). Any ideas? Its quite a loud rattle / clunk that happens between 3 - 5 times after switching off.

1 hour ago, bigshorty said:

Its quite a loud rattle / clunk that happens between 3 - 5 times after switching off.

Hi,

The EGR valve is at the back of the engine, though more to the passenger side, I think. See photo

If that valve is sticking, so a DTC is present, or generated at the time that an active or forced  DPF regen cycle starts, the regen should not start. This could lead to a build up of soot in the dpf to the point where on-car (active) regeneration is not possible due to the risk of thermal run-away.

If your car can start a regen, but  it ends with a "duration" DTC code, but no EGR DTC code, then this is not the case.

 

Fixed this problem.

Another issue with a few diagnostic trouble codes (DTC) I've been having with my car has led me to the cause of this. For this other issue, I had to have a look at the throttle valve, which I was informed was also called the anti shudder valve. On taking off the throttle body, I noticed the throttle valve was sticking against the side of the throttle body assembly, so I got a hammer and screwdriver and gently tapped the valve away from the side of the assembly. When I put it back together, started the car, then turned the car off, the rattle / clatter that I was experiencing on turning car off went away. I've had to switch the car off a number of times now and the rattle / clatter has not happened again, plus the DTCs for the other issue I was having don't seem to appear anymore either. Two birds with one stone!!