DarrinWrx

On MY96 Impreza there is a high pitched tapping noise from the engine.
It sounded like it came from the LH side of the engine...already checked cams, valves, springs.
But still the sound remains, it increases with revs and is always present. It sounds like something metallic near the inlet manifold area...which is opening and closing very fast,
Fault diagnosis shows the crank sensor and the throttle sensor are faulty (or their wiring), could this be the problem caising something to act up???

The mods are full st exhaust, induction kit, FMIC.

Please help people, I don't want to send it to a garage and end up being something simple like the wiring for the sensors.

Cheers,
DarrinWrx.

merlin24

iTrader: (1)

Valve clearance too big ??
Noisy Injector ??
Exhaust gas leak from headers/up-pipe/turbo ??

Mick

NUTTYNICK

Have you had the cambelt done or the heads off recently?

Has it just started happening or something that occurred after something mechanical was done/changed?

I know injectors can become quite noisy at times but it's difficult to tell over t'internet

DarrinWrx

Valve clearances all ok, as I checked the cams, springs and valves all fine.
Didn't know that injectors could do this sort of thing, will check them too.
The sound is mainly central and above the engine block, with a high pitched clicking sound of tapping.
This sound was there before I took the head off to check things out, as someone mentioned the springs (clearances wrong) to me before...so I checked them, even replaced the cams, springs and discs...but the sound is the same, no better.
Otherwise engine is running nigh on perfect, except that is was stalling at junctions, but the throttle sensor isn't working correctly which would explain the stalling.
Any other ideas???, as I will be checking the sensor wiring and the injectors next.
DarrinWrx.

merlin24

iTrader: (1)

What were the valve clearances set to ??

andyxros

my purge control valve ticks like mad and is loud, just under the inlet manifold
where intercooler pipe conects to manifold under throttle body, same sound as tappets and speeds up with engine

NUTTYNICK

I was thinking bent valves, but in order for this to happen, the cambelt would need to have been changed at some point and the cam rotated.

The valves only need to bend a little, meaning they still seat correctly (ish) but contact each other making that click.

It was a common problem on the old Mi16 valve heads before people were aware there was an interference.

Hopefully it's the purge control valve though

scoobjam74

iTrader: (11)

silly question could it just be the boost solenoid on the drivers side wing as mine makes a ticking noise and that changes with revs

DarrinWrx

I'm slowly working through changing the wiring for the sensors to get rid of faults 11 and 31, have already cleaned the purge valve and will clean out the injectors too. Would those faults show up for any other reason???...ie problem elsewhere? As I did change both throttle and crank sensors, no change...so that is why I changing the wiring harness.
The sound is central, not to one side, so I doubt it is the boost solenoid. But have checked and cleaned that too just in case.
The sound is as if the throttle is opening and closing the throttle valve very fast...that is what it sounds like.
I'm sure the valves are not connecting as I've just taken off the LH head to check them...as it seemed at one point to be coming from there. But all is fine and I put the timing belt on myself correctly and the sound remained.

If after this and the sound is still there, I will be scratching my head once more.

andyxros

see if you can disconnect the purge valve while its running see if it stops bit hard i know when the intercooler is in the way

DarrinWrx

Intercooler isn't really in the way....its the damn alternator and the pump next to it that makes that a bit difficult. If I am reading the diagram correctly...it sits right under the inlet manifold....or is it the valve at he back of the engine. If its at the back, still the IC won't be in the way.
Thanks for the advice, will let you know what happens when I get around to it. As I must spend time with my wife and kids too........as she tells me that they are missing me when I'm in the garage.........oh bless.

Catchya later people,
DarrinWrx.

andyxros

small valve at back with two smal black pipes coming from it

DarrinWrx

Tried all them, it looks like it is a bearing that has gone...means engine out. Oh well, more time off the road.

Thanks for all the advice.
DarrinWrx.

andyxros

got to take mine out too soon cos big ends are failing and loosing power a little now just want to get mot out of way saturday then think what to do about engine .........just letting you know your not only one might make you feel a bit bette cos its annoying


i would of put bets on it being purge valve though mine is so ticky and annoying

ronfer

i am also getting saqme type of noise its been looked at and they reckon either gearbox or transfer box do you hear the noise when idlein

DarrinWrx

My noise is present all the time.........yep, big end gone bye bye.