1999 740i Clicking sound from engine - BMW Forum

timindp · 09-07-2010, 05:30 PM

Ok, so all of a sudden this morning when I started my car, I heard a clicking sound comming from the engine. The service engine light is on. I took off the engine plastic cover to try and pin point where the noise is comming from, and it sounds like it is near the valve cover. Any idea what his may be? Faulty valve? The car drives fine, though I did smell some vapor odor upon starting the car. I have 156,000 miles on it.

brettski · 09-08-2010, 08:44 AM

Is the frequency of the clicking sound linked to the revs of the engine?

Does the engine rev freely in neutral, or does it hesitate or struggle to make power?

Could it be an injector pin is stuck open/closed? Try putting the pointy end of a screw drive on each injector (in turn) and the handle end on your ear to isolate the sound, unless you have a stethescope type tool.

Have you check the oil recently?

timindp · 09-08-2010, 06:21 PM

Just did an oil change with synthetic oil. It seemed to go away when the new oil circulated within the engine, then about 10 seconds later, the tapping began again. Yes, it is linked with the reving of the engine. It sounds like I can hear the tapping comming from the valve cover. I can almost feel the tapping too.

witeshark · 09-08-2010, 06:24 PM

Could be noisy valves that need adjusting.

timindp · 09-08-2010, 07:46 PM

It sounds like that the noise is coming from underneath the MAF into the middle of the engine, Near the water pump or just abve it.

witeshark · 09-08-2010, 08:31 PM

That 4.0 V8 has a timing chain right? How about the timing chain tensioner?

brettski · 09-09-2010, 06:51 AM

How dirty or gunked up was the oil you took out? Was it dirty enough to have blocked some of the oil paths to the valve train?

fastbackvette · 09-17-2010, 10:22 PM

sounds like a timing chain issue to me. usually it will have a rattle sound when you start it for the first time of the day.

brettski · 09-18-2010, 01:27 AM

I did read somewhere of a car that had a ticking noise that ended up being the main serpentine belt missing a chunk of the grooved face, it hadn't actually failed, but it was well on its way. The way the other guy tracked the fault down was to put a mark on the belt to see if the mark was at a similar frequency to the mark flashing past. Its worth a look to see what condition you belt is in.

timindp · 09-20-2010, 02:53 PM

Yes, it was a timing chain. It now broke and I am out of an engine. Needs to be replaced. Going to either part out the car or sell it as is for peanuts.

brettski · 09-21-2010, 06:20 AM

Bad luck. Sorry to hear that you are parting company with it.

marti5 · 09-24-2010, 03:12 PM

You have the 4.4 V8 witch being a 1999 I reckon its the double Vanos version, so it will be the Vanos...I can explain but it will take me all night,,,Google e38 vanos..its fine to drive so dont worry..

fastbackvette · 09-24-2010, 05:09 PM

sorry that i was right on this one. the key word was first thing in the morning.

brettski · 09-24-2010, 06:32 PM

Quote:

Originally Posted by marti5

You have the 4.4 V8 witch being a 1999 I reckon its the double Vanos version, so it will be the Vanos...I can explain but it will take me all night,,,Google e38 vanos..its fine to drive so dont worry..

Good to see you back Marti.