E30 Zone

Hi Folks,

My iS has developed a clicking noise coming from the glovebox area.

It starts at 3000 rpm at a frequency of about 1 a second which increases with engine speed until it stops at 4000 rpm.

Anyone any ideas what it is or if anything is likely to fall-off / explode?

Cheers

Timing chain.

Yep.

Timing chain wear or tensioner is shagged. Both make the same sort of noise. And the rev range is exactly right for the noise to manifest.

Hope not ! It had a tensioner about 3000 miles ago. Chain, guides and sprockets all looked in order when the timing cover was off getting a top gasket kit at the same time —a or so I was told. Perhaps the mechanic was being a lazy so and so!

It really sounds like the clicking is coming from the glovebox / area, but I guess these noises can carry different ways into the cabin. The noise is more intermittent after a good hoke round the M25 the last few days! . I haven't been able to re-create the noise while I've had the bonnet open yet. It should be pretty obvious that it's coming from the front of the engine then, right?

Get a garden hose and stick one end to your ear and probe the engine with the other

Well, even though it had a new tensioner and the other timing assembly checked. It could be that the mechanic was going to do the chain but gave up when he couldn't crack the crank pulley bolt since they are VERY VERY tight!

I replaced the whole timing chain assembly on mine and cracking that bolt took the most amount of time out of the whole job

If it was a LHD iS, ticking coming from behind the glove box would suggest a cracked maifold or blown gaskets on this or the down pipe. But this ticking is more appartent under load and below 3000rpm.

The 3-4K tick is the main symtom of timing chain trouble (Hence the abrupt post previously, lol) since the engine is just coming on cam putting pressure on the parts and also probably due to resonance from the parts to an extent.