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RockJock
06-04-2009, 08:40 PM
A friend has a 91 E32 M30 with about 110K miles. I noticed a ticking that is audible above the deep rumble at idle from inside the car with the windows closed. I used a long PVC tube to listen along the valve cover but I couldn’t isolate the sound. So I tried the same thing along the fuel rail and I could isolate a dull clicking/clacking above the second injector from the firewall. It's a tad more distinct with the motor at operating temperature. I’m wondering, can they really get that friggen noisy? It doesn’t appear to be leaking either as there is no fuel odor.….Where should we start?

russiankid
06-04-2009, 08:44 PM
They do get fairly loud. You may also be do for a valve adjustment.

Blitzkrieg Bob
06-04-2009, 08:45 PM
Yeah, the old injectors on my M20 were louder then the lifters.

I ended up replacing then.

BigKriss
06-05-2009, 08:17 AM
yeah they can get noisy its normal.

ArnZ!
06-05-2009, 08:22 AM
Since were on the topic. If an injector o-ring is leaking doesn't it leave evidence on the intake manifold? Cuz some of them on mine have a blackish substance in the little valley before the injector hole. Also on cold start i can smell fuel soooooo strong.

e34.535i.sport
06-05-2009, 11:37 AM
A friend has a 91 E32 M30 with about 110K miles. I noticed a ticking that is audible above the deep rumble at idle from inside the car with the windows closed. I used a long PVC tube to listen along the valve cover but I couldn’t isolate the sound. So I tried the same thing along the fuel rail and I could isolate a dull clicking/clacking above the second injector from the firewall. It's a tad more distinct with the motor at operating temperature. I’m wondering, can they really get that friggen noisy? It doesn’t appear to be leaking either as there is no fuel odor.….Where should we start?

Dont know where you are but I have my old set out of my 535i which I changed over for a set of Bosch Design II's recently... I was suspecting some leaking but they were really quiet.

I was gonna get them sonically cleaned and sell them on, just haven't got aroud to it yet... Let me know if you're interested! :)

RockJock
06-05-2009, 06:06 PM
Maybe it’s normal? The only reason I noticed it was because it’s significantly louder than the M30 in my 535i. He said it’s been doing it for as long as he can remember. Perhaps we’ll start by having a look under the valve cover (check the banjo bolts; oil starvation); do a valve adjustment, which is something I’ve never done before and I suspect it’s far trickier than simply following the instructions on a ‘HowTo’ document. If she’s still ticking/clacking then we’ll take a peek at the injectors……wish I had one of you E34/E32 gurus close by so I could bribe you with a few beers ;).

RockJock
06-05-2009, 06:09 PM
Dont know where you are but I have my old set out of my 535i which I changed over for a set of Bosch Design II's recently... I was suspecting some leaking but they were really quiet.

I was gonna get them sonically cleaned and sell them on, just haven't got aroud to it yet... Let me know if you're interested! :)

Western Canada; I'll let you know the verdict as soon as something shakes out....thanks kindly :)

tim eh?
06-05-2009, 11:03 PM
they are pretty loud on my m20 - i wouldn't know but everyone tells me it is normal.


Yeah, the old injectors on my M20 were louder then the lifters.

I ended up replacing then.

what happened when you replaced them bb?