ticking?

[grayg40]

hey lads
i seem to have developed a loud ticking noise like a buggered tappet or a bent valve. (Noise coming from top end back/middle)
It started after i let the car sit over the weekend. Started the car monday for work and there was a loud ticking and missing now and then, it cleared after about 2 mins so off i set thinking it was a sticky tappet, just about at work (30 mile drive) and it started again but just now and then. Got home monday nite and changed the tappets, then it was contsant 
so lastnite i whipped the head incase i had a bent valve, stripped everything, dial gauged the valves and nothing. Regound valves and put her back together, still the thing ticks
Oh i also checked for jumping spark from the leads and plugs in case it was a spark issue.

Could this be a faulty injector?
Didnt have time to check as it was pretty late by the time i got things finished so far!

Any suggestions gratefull!
Mark 

[scotsjohn]

Sounds like what I've got too. Top end's OK so I reckon it's an injector like you said.

[youngprodigys]

check all the manifolds are done up tight and sealing, dont half make a ticking sound if theres a slight leak!

[scotsjohn]

One of the first thoughts to cross my mind, but my manifolds haven't been moved since I bought the car a few years ago.

[AlexG40]

It could be a blown exhaust gasket.  Check your cam timing too.

[grayg40]

i did check the folds before but it goes down a cylinder when it starts ticking so thats why am now thinking injector.
it didnt tick today on the way to work or back but it did when i started it at dinner time for a min then went again. if it ticks again i will disconnect each injector at a time and see what happens failing that i will have to dig deeper

[vwmk3jon]

mine ticks too. I put it down to the injectors.

[ereeiz]

If you haven't got a stethoscope then get a large screwdriver and put it to your ear, put the metal end on the area you think is ticking. It transfers the noise/ vibration through it so you can pinpoint noises.

It works better with a small diameter hollow metal tube, but a screwdriver is good as a guide!

[Etches]

All all my Gs the Injectors have ticked

[hayesey]

any multipoint mk3 engine I've had has had ticking injectors.  I've had the lot, NZ, GT & G40

[xandyx]

when you replaced the tappets, did you left them sitting on oil for a few hours? what oil are you using?

[grayg40]

have used the screw driver method. am an engineer and overhaul turbos and hydrolic speed controls for the oil and gas sector so i have a knowledge of mechanical stuff. i know the injectors tick but this is loud.
would a knackered tappet cause it to miss half a cylinder, i say this cause if i pull the the injectors off 1 by 1 the noise is still there and it goes off a full cylinder and same with the plugs leads but the ticking is still there.
also could it be spark jumping between the lead and the part that actually goes on to the plug.
Andy yes i did,
had the car nearly 7 years and never come across this one before. am getting a bit stumped.

[hayesey]

I'd check the cam timing, this sounds a bit similar to what happened to Alex at a track day recently.  His bottom cam pulley had come loose causing the belt to slip and a valve hit a piston

[AlexG40]

I'd check the cam timing, this sounds a bit similar to what happened to Alex at a track day recently.  His bottom cam pulley had come loose causing the belt to slip and a valve hit a piston

Actually 4 valves hit 4 pistons....but yeah, make sure your cam timing is still correct to rule out the worst. Though if you've had the head off...make sure the crank pulley is not able to turn on the crank.

[grayg40]

cheers for the advice lads , the timing was correct, it was just a weird tick. went out one morning last week and no tick,