01 4.3 Dies misfires...HELP!

Zembonez · October 30, 2002

HELP!

My 2001 4.3 AT Silverado (53K) occasionally has a miss at highway speeds. This symptom comes and goes. Also, twice it has sputtered and missed until it died and would not restart while driving on city streets. When it dies it seems like it has "jumped time". It spits back through the intake and turns over irregularly. Both times it was towed to a dealership. The first time they installed a new cap and rotor and charged me $250.00 for the pleasure. I was out of town so I had no choice but to pay it even though I was not too convinced that was the problem. The truck ran fine after I picked it up for a while.

The second time this happened the symptoms were exactly the same. The second dealer said it was due to an AC line dripping condensation on the dist cap and causing it to "short". They covered the AC line and sent me on my way. After this "diagnosis" I look back and it did seem to run like it had moisture in the dist cap. (much like washing an old engine and getting the dist wet) It ran fine after they added a cover to the AC line to divert the dripping water...for a while... then the symptoms appeared again driving down the highway. I feel like I am just waiting to have the same problem again and I am tired of having this truck towed! Anybody have any suggestions? Could this be an EGR problem?

Obviously I need help... but wait... thats another forum. GRRRR!

2001 HD · October 30, 2002

My 2000 1500, 4.3 had a similar symptom. Missed on excelleration, backfiring, hard/no starting. No SES light or codes. Ended up being the fuel pump. Might check to make sure they got the dist cap tightened down good. The loc-tite on the screws that come with the cap make the screws hard to thread in. Almost feels like it's cross threading.

Could be leaking/sticking injectors. Dump a can of Chevron Fuel injector cleaner in and see if it helps. An intermittent fuel pump can be hard to diagnose unless you have a fuel pressure gauge.

Zembonez · October 30, 2002

Thanks

I will get that pump pressure checked to see if it is within specs. I have noticed a "different" noise coming from the pump. It has a high pitched sound that it didn't have before... and the noise comes and goes! That might just be it! Gotta fix it... I just love the truck.

Off to the fuel pressure gauge as we speak.

Cop_Dodger · October 31, 2002

This is a common problem with the 4.3L. 90% of the problems are from distributor cap and rotor. The reason for this is the A/C system. There is an A/C hose that runs right over the distributor. This hose gets condensation on it that drips cold water onto the distributor cap. Water then condenses on the inside of the cap causing currosion. Try looking under the distributor cap and rotor. Chances are it's curroded. You'll need a new cap and rotor.