Hello All,

I have read the various posts on the subject of engine noises from the 7.3 idi. However, none of the posts I've read seem to match exactly what I am hearing from my engine. The best description I can give is that it is a hollow tapping sound -- like tapping a tin can with a mallet and not too different from that of a lifter -- and seems to be in time with the engine's cylinder firing (don't know which), it is faintly audible at idle speed, increasing with engine RPM, most audible under slight engine acceleration. I have used a long screwdriver, my ear to the handle, to see if I can pinpoint the source, to no avail. The engine, starts and runs fine. The truck has over 200K miles on it, no oil consumption issues. Thinking the noise was coming from a noisy lifter, just prior to changing the engine oil 1k miles ago, I ran some Sea Foam through the crankcase for a hundred miles, or so. This had no effect on reducing the noise. I also removed and cleaned the breather's 'sardine can,' located just behind the intake hole. My concern is that it may be something more serious than a lifter. Perhaps, an injector going bad, but I don't know what sound an injector makes when it is going bad or about to fail.

Your comments and suggestions would be greatly appreciated.

Cheers,
Norman C

 

to test if it the injtor while the trucks is runing crank them open one buy one if the noise gose away them u know in injector

 

OK, that seems to be a good way to test the injectors for effect on the noise. It may also assist in pin pointing the noise, if it is not an injector going bad, but some other source.