Ive got a 1998 bravo hgt its developed a knocking sound on the engine , sounds like a cam or a piston possibly oil pump has gone if anyone has had the same problem please help, thanks

if its really a knocking sound then most probably you have an oil pump failure and theres no oil circulating in your engine block anymore. chances are your conrods have gone south on you.

if your engine sounds like a diesel engine during cold starts in the morning minus the knocking sound then it may just be your cam variator.

if its a 98 then its pre variator iirc.

mountainmachine said:

if its a 98 then its pre variator iirc.

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are you sure? if you just mean the 147 models they still have VVT, which is what i assume you mean by variator?

Thought the VIS part was to do with the variator and VVT(variable valve timing) thought that was one of the changes made pre to post VIS, perhaps it was on the variator system and not the addition of a variator, meaning of course i was wrong in my assumption.

thanx for all your replies, my engine makes the noise on start up doesnt when idleing but when you rev it the noise is there could that be the oil pump which rattle`s .

mountainmachine said:

Thought the VIS part was to do with the variator and VVT(variable valve timing) thought that was one of the changes made pre to post VIS, perhaps it was on the variator system and not the addition of a variator, meaning of course i was wrong in my assumption.

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the VIS is just like a big valve on the intake manifold that opens at high revs to let more air into the engine, i dont see why you dont just fix it open :chin:

with this knocking as i said its there on startup not there when idle when revved or driven its there, also the engine temp goes high no loss in performance it drives as normal would it be worth my while putting engine flush through it to see if that free`s up any oil ways, if any other ideas would be really appreciated beleave me ( i miss my hgt ) my other cars are slow its just no fun driving to work anymore.

bulldog5046 said:

the VIS is just like a big valve on the intake manifold that opens at high revs to let more air into the engine, i dont see why you dont just fix it open :chin:

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Because for better low down performance you want a smaller induction pipe. It will allow faster air speed through the induction system thus resulting in faster pick up below say 3,000 RPM this however once the engine is at higher RPM restricts airflow and hence the VIS system opens up the bore.

:yeahthat

you lose loads of torque with it stuck open.

i appreciate what your saying but how does that effect the engine enough to make a knocking sound

a rattle like you describe could be many things, without hearing it for myself its impossible to narrow it down.

a decent mechanic will know what it is just by listening so pop to a few garages and get some free advice.

I got some free advice my mechanic said it could be cam , piston or oil pump so im back where i started , if anyone could recamend a garage in the cardiff area

you can easily rule out or confirm camshaft bearing problems, check for play in the camshafts, and see if the noise is significantly worse with the oil filler cap removed, or even the rocker cover (but be careful).

a piston wont make a knocking noise, i guess you mean the conrod due to play at either end of it, thats a bit more difficult to tell apart from an oil pump noise, and more difficult to check for.

where do you live? i'm happy to have a listen if you're close enough.

hiya jug i live in the wales area let me now

i'm in durham, north east england, its too far, sorry.

no worries thanks for the offer i appreciate it.