1996 Chevy K2500 Won't start

[ZGM]

For the past month or so my truck has been chugging at take off until it shifts into 2nd. Then at about 55 mph it will chug again. It idles fine. Yesterday i went to start it and it would turn over, then freeze and not start. Also makes a popping sound when trying to start, smells like sulfur? The check engine light has been going on and off. help!

[John_and_Donna]

Originally Posted by ZGM

For the past month or so my truck has been chugging at take off until it shifts into 2nd. Then at about 55 mph it will chug again. It idles fine. Yesterday i went to start it and it would turn over, then freeze and not start. Also makes a popping sound when trying to start, smells like sulfur? The check engine light has been going on and off. help!

How many miles on the truck? Has the fuel filter and/or fuel pump ever been replaced?

Even on the newer rigs, when it won't run or start, the problem is most often either spark or fuel. I'd suspect fuel first.

Ours just died on us one day; ran fine in the morning - drove to work & parked it - at lunch it would not start. The fuel pump was the culprit on ours. I have since learned that it is a fairly common failure in the Chevy trucks. The pumps work fine for a long time, then suddenly quit. We had close to 138,000 on ours when it happened.

From what you describe, it could be the filter getting clogged. The sulfur smell should be like rotten eggs. When you smell that, it is an idication that the mixture is off - usually on the lean side with the modern engines. A lean condition can occur when you run out of fuel, like when the filter is clogged and/or the pump isn't pumping enough.

A good tech can diagnose what it is real easy - the pump or the filter. They have a way to do this with the Tech II at the dealership.

If fuel is OK, then I'd suspect either timing being off or you have some bad cylinders (either plugs or wires).

[Itstali25]

Just something to think of, i'm pretty sure rotten egg smell can come from the Catalytic Converter being bad which would explain the check engine light. I dunno, i could be wrong just something i thought of.

[shopratles]

I would check the "CAT" also. Here in TX we have smog testing. Last year my '90 Sierra failed. Took it to muffler shop and they used their temperature sensor on the exhaust pipe before and after the "CAT". Don't remember the exact readings but there was a huge difference in the temp reading - "CAT" was becoming plugged. Replaced "CAT" and truck passed emissions fine. Easy check and most Exhaust shops will check for free. Good luck.