Knocking noise coming from engine

[s2_bo]

Cheers for all your input guys.

I will check the cap again later. I dont think its a shot bearing because i have done over 300 miles with it like this and its not chewed anything up yet.. :s
Saying that at first i thought it was gearbox related as i thought it seamed to be coming from around that area. But now i'm not so sure. I dont think its a pump though, as the noise is defo coming from the rear of the engine.

Will take it for another drive in a sec.

Thanks again for any help.

Bo

[Rusty]

Can't say I'd like to drive it taht much with a noise like that, if it's internal and it does go then you're a bit phooked...

[s2_bo]

Yeah true. Well im prepared to risk it, i would just like to find out what the problem is, was planning on stripping it down this weekend when i go to work on the S2 anyway. So if i cant sort it before then it will get a trip to north devon and then ill take it apart properly to try and track this problem down.

Will try the light down the spark plug channel idea tonight.

Cheers.
Bo

[shark_90]

Come to think of it my 1.8T A4 made a similar noise when the cambelt jumped a notch. But you say it is boosting OK?

[s2_bo]

So could it be a piston hitting the valves?

Or would that be more like 4 or 5 notches?

it's boosting fine. Stronger then ever with the new bov

[A80Avant]

i had a similar noise but mine where the tappets as it was identical to that,and only happened when hot/warm.However i wasnt loosing any water in the oil cap.Was loosing water elsewhere.

The fact that you have water there+the noise,i would suggest that you look into it before it gets any worse.There could be a crack somewhere there building up with the thermal differences,and you wouldnt want that to end up being unreperable.

[shark_90]

No I don't think it's contact mate otherwise you'd have some serious running issues, I think it's more likely to be a slap or knock (not sure that "knock" is the right technical term to use - my engine knowledge is quite novice).

[WabTheKing]

had a similar noise on an mr2 turbo, no loss of boost, everything else fine - snapped crank due to a bad regrind which produced a stress point, car ran fine because of how it snapped, held its self togther

[ryster]

it would n't be anything to do with the dual mass fly wheel would it
just an idea because thats down that area

[s2driveruk]

no idea Bo but i have to say it doesn't sound healthy at all. Personally wouldn't be driving it hard anywhere at the moment. Hope you get it sorted and it turns out to be something relatively minor

[WabTheKing]

buy a cheap automotive stethoscope then you will have a better chance of pinpointing the area which it is coming from

[s2_bo]

is it worth taking all the plugs out and turning the engine over to see if any water sprays out of the spark plug channels?

[WabTheKing]

would be worth taking them out, dont think u will get water tho, spin it over without the plugs and see if you can identify which cylinder - if any it is coming from

[anton]

in my experience a knock like that is always bad news, its too fast to be in the head....my mains failed on my car and sounded like that, took about a month of me trying to figure out what was happeneing with it getting very slowly worse, then all of a sudden over the course of about half a mile it went from a barely noticable knock to a full engine sieze, on the motorway that is VERY scary! IMHO do not drive this car! i wouldnt even rev it let alone put load on it.....
Another car i know of had a strange knocking sound that turned out to be a metal peice of the headgasket that had broken off and was bouncing around, managed to write off a piston with just revving the thing....but to be honest that would give some serious detonation before very many miles.....either way its not worth the risk in my opinion...yes it may be just a simple problem, but if there is a rick of causing serious damage do you really want to risk it?!?!?!

Ant

[DJones]

Not nice, the noise is to slow for it to be coming from the cams. Definitely crank assembly related. Though I once had a similar noise coming from a knackered clutch release bearing..

You could also try changing the oil to see whats in it before pulling it apart, Just a thought..

On the water in the oil front, there is a kit you can buy to see if you have exhaust emissions in your expansion tank, it can give you a good early indicator of head gasket failure before it damages anything.

Hope its not major.