What's that noise??

[janos1]

I have a noise that resembles a wristpin tapping. How would I be able to check the fuel system to make sure that its not a fuel related problem.

 

[argve]

loosen the nut on the fuel line at the injector one at a time and see which hole is causing the tapping.

Then if loosening the injector nut makes it stop, then I would swap that injector with another one and repeat.

If problem stays with same injector = injector causing the problem.

If problem stays with cylinder then we know it's something else.

Then I would pop off the valve cover and have a look see. Might be the start of a valve problem. Look for soot build up around the valve spring.

Report back what you find.

 

[janos1]

Thanks, I'll give it a try.

 

[The Warden]

I would loosen each injector line at the injector until that cylinder stops firing, one at a time, and tighten them afterwards. When the noise you're hearing disappears with the cylinder no longer firing, you've isolated the noise to whichever cylinder it is. Then, swap injectors between two cylinders, and do this test again (just on these two cylinders). If the noise "followed" the injector, it means there's a problem with the injector. If it stayed with the same cylinder, it could indicate an internal problem in that cylinder.

If the noise is inconsistent and/or doesn't go away at all when you loosen the injector lines, that would indicate to me a problem in the injector pump.

Hope this helps some...good luck! It's 0430 after I worked a 15 hour day, so I hope my reply was comprehendable

{on edit} Oops, looks like Travis got his response posted while I was trying to figure out what words to use...of course it's morning for him while it's still night for me

 

[janos1]

Would a dirty fuel filter starve the motor at highway speeds and cause a knock?