Noise from engine bay when engine is stopped!

[pingpongpo]

Hi guys,

I've just been out today doing some work on the car (servicing the brakes, new front lamp) and I noticed that when I came back from a short drive and stopped the engine, after about 3 seconds when everything was quiet I heard a noise which can only be described as a clonk from the engine bay.

I thought this strange as nothing runs on for that long after I've switched off so I popped the bonnet and tried again, this time I just turned the key to make the dashboard indicator lights come on and then switched off again, sure enough, the same noise and I think it's coming from underneath the vanity cover on top of the engine.

Is there any solenoid valves or anything under here that could be on there way out or perhaps something else a bit more terminal?

Details - Golf '52 reg PD130 (FSH) 81,000 miles.

Many thanks,

Simon.

[BW2309]

It will be the Soft Stop valve.

This is mounted next to the EGR valve.

It's function is to shut when you turn off the key, it shuts off the inlet so the engine runs to a stop in vacuum. This means no air gets into the cylinders to compress. This makes the engine stop gently and quietly rather than shuddering abruptly to a stop. It also reduces the forces on the timing belt that would otherwise occur as the engine stops due to the hige compression.

After a few seconds it flaps open again ready for starting.

If you lift the engine cover you can see it, right next to the EGR, it has a small lever on it's side - looks kinda like a throttle valve. It is just where the plastic inlet pipe meets the alloy inlet manifold.

[pingpongpo]

Cheers mate, that sounds a lot less costly than my initial thoughts about the fuel solenoid!!

I assume it is on it's way out if it has started making noises so I will enquire about how much a new one is.

Just need to figure out how to get the engine cover off now

[BW2309]

LoL

Engine cover just lifts off!

There is no fuel solenoid external at all, that's only on the old rotary pump engines from years ago. The old 90 and 110bhp's.

Yours has Pump Duse system, one unit injector including it's own pump per cylinder. It's all fitted inside the cylinder head, even it's fuel supply and so you can see or hear very little from the fuel system.

As long as the valve is actually working it'll be fine. They sometimes become a bit vocal when the vacuum diaphram has gotten a bit old but IF it's still working you only need to swap it if it's annoying you.

If you know anyone else with a PD engine and you wanna screw them up for a laugh just zip-tie this valve shut. The engine will crank and sound as though there's no compression - then simply laugh as they begin to break down in tears at the thought of the severe engine damage they suspect!

Very simple and good for a laugh! Don't forget to tell 'em after though eh!!

There's a unit similar on the very late 1.9TDi 105 and the 2.0TDi's but on these engine it's actually a throttle valve so don't anyone mix the 2 up - they do very different jobs!!