2000 Silverado missing problem

[JWI Racecars]

Hello everyone, I have a problem with my 2000 Silverado with a 4.3 V6 and 5 speed trans.
The problem is a intermitent misfire/ engine cut out.
I replaced the plugs, wires, cap, rotor, coil, ign module, and even tried a new computer. then I took it to a GM dealership and they said Crank position sensor... so I put one of those in too..... still missed, so I took it back and they said there was a bulletin about the crank position sensor contacting the reluctor wheel in the front timing cover. they said it makes the computer think you're spinning like 10,000 rpm and cuts the fuel pump out, They said to replace the cover or shim the sensor.. So I let them shim the sensor.. worked long enough for me to pay the bill and make it home. started again... so I pulled the sensor and replaced the shim they installed (rubber o-ring) with a spacer I machined out of aluminum.. worked OK but I still have a slight chug/ miss... It kinda feels like when you're fuel filter gets clogged on a Carburated car....(replaced fuel filter too)


Sorry this post is so long... But I am frustrated to say the least... any thoughts????

Thanks for any help,
Joe

[6869704X4]

I would love an answer to this too.
My daughters 2000 Blazer 4.3 with auto trans is doing the same thing. I have replaced everything you have plus the cam sensor and fuel filter. I didnt try a new computer though.
It started with a code showing #3 cylinder misfire, now it throws a code showing random misfire.
I guess I'll start over.

Oh yeah does anyone know of a good service manual? Do I need to get one from the dealer. I hate trouble shooting by throwing $parts$ at it.

[JWI Racecars]

Mine showed #1 and#6 miss fire than went to random. drove it again today and it seemed like it was worse.... it was raining and the roads were pretty wet..??? wouldn't think that would make a difference though...????

[6869704X4]

Well, I borrowed one of them there fancy Snap-on Solus machines. It took me a while to figure it out(Now I know what a dog feels like watching TV) but it showed a couple of more codes. P1107 MAP sensor circut intermittent low and P1351 IC circut voltage high/open.
The machine has a troubleshooting feature that I'll play with today.

[erikj]

Any luck finding out what was causing the misfire? I have a 2001 4.3 liter silverado that is misfiring on #2 cylinder. Cap, rotor, plugs, wires, cam sensor, crankshaft sensor and distributor were replaced. Checked injectors and timing chain, both seem good. I'm going to try a new computer to see if that will work.

[BACKYARD88]

I don't know if this will help any of you but there are two common problems with the 4.3 both in the full size trucks and the s/t series. Seems like you all have corrected these but I'll put them out there anyhow.
1st, make sure your coil wire is routed OVER the rest of the wires as this will often cause a misfire/no start condition.
2nd, inspect the inside of the cap for moisture, this is especially common on the full size trucks. If you find moisture inside the cap dry it out, there are one or two small holes in the plate on the distributor that the cap bolts to. Make sure these are clear of Debris. The cause of this moisture is condensation dripping off of the ac tube that is routed directly above the distributor. GMs correction for this is to install a section of insulation on the exposed aluminum pipe over the cap.

[6869704X4]

To make a long frustrating story short, mine turned out to be the #3 plug wire.

[erikj]

Thanks for the replies. I will double check the wires.

[laidout]

2nd, inspect the inside of the cap for moisture,

that is the main problem i had a 2000 and the dealership said the condsation off the ac line will drips on the cap i got the cap changed and it didnt do it again

pluc they put something over it to divert the water

[killer71]

not sure if this will help or what kind of intake you have but my 03 burb did the samething and the intake had to be replaced (plastic).

[Kurt L]

i'm having the same problem with wifes 2001 blazer,changed out the wires,cap rotor button even the module.stills misses every once and awhile.can y'all help me here with this it's driving me and wife crazy.even replaced plugs and gapped them.