Question on Injector Noise - not 914

[Tidybuoy]

I'm hoping that someone in here can help. My 914 is so noisy that I would never be able to tell if the valves were ticking. However on my 1988 BMW 528e, I have had a persistent ticking. The car runs perfect (except the noise).

I just had my valves adjusted because the engine was moderately ticking. The shop (very reputable & has worked on my cars for years) told me that the ticking won't go away completely because some of the noise is coming from the injectors - solinoids opening & closing.

I don't remember the injectors ticking when the car was new. But with 150,000 miles, I supposed this could be due to the injectors getting older. It's not that bad and can barely be heard when the hood is shut -- but, when the hood is open it's loud & clear & sounds like S#@t!

The engine definately quieted down after the valve adjust and runs better too. But the very slight ticking noise is bugging me.

I know that this is not a 914 question but I have found that most 914 owners are great mechanics.

Any advice would be great......................Vern


I also just changed the timing belt, water pump, o2 sensor, all vaccum lines, plugs, cap & rotor, wires, & fuel lines.

[914GT]

Vern, I'm not familiar with BMW injectors but typically they are isolated from the manifold and from the fuel rail by rubber isolation grommets. These are separate from the o-rings which seal on the high pressure side. Since it's a 1988 model I suspect these rubber parts are compression-set or have hardened and are not isolating the noise. Might be worth replacing all these pieces and giving the injectors a good cleaning and inspection at the same time.

[Dave at Pelican Parts]

You can also use the "mechanic's stethoscope" trick to try to isolate the noise. You can use a piece of vacuum hose; put one end at your ear and move the other around until you can locate the noise. Or you can put the handle end of a screwdriver against your head right in front of your ear, and rest the other end on the various suspect pieces. That should transmit the noise right into your ear.

You have to do all of this with the engine running, of course, so be careful of moving parts! (E.g., don't wear a tie...)

--DD

[Tidybuoy]

Would a bow tie be ok (lol)?

[914GT]

Only when working on a Chevy.