GMScott

Any help would be greatly appreciated!!

Just developed a very LOUD engine knock. 114k miles. The 2nd lift pump was just replaced after limping home from FL. on an average of 4- 6 lbs. of fuel pressure and now THIS!!

No visible problems, no performance issues, no dip in oil pressure, no elevated temp. Actually, the truck runs great. Yeah, I know, they always run the best before blowing up.

Hard to determine where knock is coming from. Being a backyard gasser mech, I would describe the knock as sounding like a stuck lifter.

Someone told me a bad injector pump could make a similar knocking sound.

Funds are limited as I've been unemployed for over a year so anything I can check myself would be helpful. Up to now truck has been used as very light duty. I had to put it to work to earn it's keep towing and now this!!

Thanks for your help

Haulin_in_Dixie

Use a 3/4 wrench and with the engine running loosen one injector nut at the head at a time til the knock goes away. You can check the injector by switching two of them and see if the knock stays at the same cylinder. If it does, the engine has to come apart, it is either a rod, piston, or scuffed cylinder wall. When you find the right cylinder about the only other thing you can check is the pushrods and related linkage.

GMScott

Haulin - thanks for your response and ideas. I'm gonna try that first thing this morning. Guess I better hold onto my butt or should I say my savings account, cause I bet this is gonna hurt!!

Just can't believe that I can drive this truck for over 100k without any real problems at all and now that it's off warranty the crap hits the fan and it starts falling apart. I just rebuilt the tranny and replaced the TC for $2,600.00 last month. Of course that problem came about after the warranty expired too.

Jerry

edited by moderator