Knocking in 4.3L

Greg · February 8, 2002

Our 4.3L S-10 has developed an engine knock which is most pronounced under light acceleration at low speeds, especially when warm after running it at speed. I noticed it the first time after about a 90 minute run at highway speeds slowly driving up my son's 1/4 mile drive. That was at about 350 miles on the odo this afternoon. When we picked up my Av tonight, the service advisor heard it but all their techs had left for the day. The knock seems to be coming from the rear of the engine compartment, matches revs, and sounds internal to the engine. Ideas? Probably not good, eh? My son is supposed to go about 220 miles round trip tomorrow and wonder whether he should take the S-10.

bassdog · February 8, 2002

Greg, there are a few threads throughout the board about knocking. RyanbabZ71 would know more about it I think.

Shaners · February 8, 2002

I'm sure your son can make the trip provided there is good oil pressure. The knocking sound isn't good, but GM does have a wonderful roadside assistance plan if he needs it... (I doubt he would)

I certainly would take the truck in to have it looked at when the tech guys are there...

Greg · February 9, 2002

An engine tech at the dealer had a listen this morning. The sound is loudest underneath and is coming from the lower rear of the engine or flywheel area. Not a good place for a knock to come from! Since they don't have shuttle service on Saturday, I'll drop it off tomorrow - assuming my son and his reserve buddies ever let me have my Av back.