I've got a crunchy clunk. Starter related?

[Iwantoneofthose]

Hi,

I have a MKI CMAX 1.6 petrol, manual, Zetec on a 58 plate.

It has an unusual noise coming from the engine bay area, which happens once in any one journey, usually about 1 minute from setting off.

It seems not to matter whether I have parked with the handbrake on, or in gear, or I start driving in forward or reverse. The only consistent factor I can see is the starting of the engine. Once it's done, it never occurs again until the next time I start the car. Performance is fine, gear changes smooth, a perfect drive IMO.

Any ideas would be very welcome.

cheers,
MB

[JAHetfield]

Can you narrow down where abouts in the engine bay the noise is coming from? Would help a lot with diagnosis.

Random guess off the top of my head, sticky starter pinion? Cure is to remove the starter and apply a liberal dose of WD40 around the pinion and shaft.

[Iwantoneofthose]

It's difficult to pinpoint, as I am driving at the time.
It is only a brief noise < 1 second, but is accompanied by a vibration through the pedals.

[JAHetfield]

I've seen a rather funky system whereby you attach loads of sound sensors to various parts of the engine then you can sit in the car with your headphones on and flick between the sensors as you drive. Not something I own but would come in handy sometimes lol.

Do all the pedals vibrate or just one or 2? Could it be a loose engine/gearbox mount? Is anything in the engine bay coming into contact with the chassis/bulkhead/body shell? Does the noise go away when you press the clutch pedal? Could it be the cat or exhaust rattling? What is the condition of the exhaust rubbers?

Sorry not much help, just trying to run through all the things in my head that it could be.

ETA could it be something like a sticky idle control valve/EGR valve slamming open/shut?

Edited by JAHetfield on Wednesday 16th May 21:04

[Iwantoneofthose]

JAHetfield said:

Random guess off the top of my head, sticky starter pinion? Cure is to remove the starter and apply a liberal dose of WD40 around the pinion and shaft.

This feels right to me.
It sounds a bit like driving over a loose man-hole cover - a bit metallic, and feels like something is releasing, so would fit right with your first suggestion.

Thanks.

(any further ideas also welcome...)