backyard03gmcguy

So the other day driving to work my truck started sputtering and back firing. To avoid stalling in the middle of a turn I gave it gas and the engine lost power, stalled and rolled to a stop. The engine would crank, start and have a very rough idle till it eventually stalled. If you stepped on the gas at all it would die. In addition to that, the check engine light was already on for a large evap emissions control leak( suspect, vent valve solinoid). The check engine light had been on for a couple thousand miles with a cylinder misfire and the evap code. I ran it cause it made no difference in performance. The symptons this particular day would last five to ten seconds.

I took off the air filter and checked as many vacuum hoses as I could find. I started it and looked under the hood , no hissing and same symptoms. I tapped lightly on the fuel filter and surprisingly she ran good for about a mile and then stalled again. I tapped it three or four more times along the way and got it home. I changed the fuel filter and she ran like a champ for ten solid minutes from idle to four or five thousand rpm. I played with the pedal trying to repeat the problem. It ran so well I thought I fixed it. An hour of sitting in the driveway off, and a trip around the driveway the symptoms returned.

I read the codes and got a po445 and a po449.

One was for the purge valve solinoid and the other was the vent valve solinoid. No codes for misfire or evap leaks. I changed the vent valve solinoid and couldn't get a purge valve before the part stores closed. Im under the impression that should not cause the truck not to start.

I thought gas, so I put some in to make sure it wasn't out and to see if the gauge was wrong, no dice. I emptied the new fuel filter into a glass, no water and very little, very fine, sediment. I figure the sediment is from the rusted threads on the fuel line nuts ground into the treads of the fuel filter. I checked for fuel preasure at the fuel rails by using the ''fuel pressure check valve'', I had fuel at the rail and it squirted out so I have pressure too.
I then started looking at the ignition system. I checked the coils and wires for spark. I stuck a screwdriver in and got a spark at all 8. I checked the plugs, the gap was .06, and it had very little black grime around the bottom of the threads and they smelled like gas. I put in 8 new plugs.

Surprisingly, it won't even start. I can hear it gasping for air with the air filter off. I have spark and fuel but it won't start. Its turning over but no longer catching.

This could be altogether separate but, I noticed the park/reverse/neutral on the dash was dim. I tried to start it in reverse, no start, neutral no start. Its either a new neutral safety switch or an adjustment. Could that cause it not to run? I'm not sure.

Anyone have any ideas or see any checks I missed? I seem to have the basics in order, air, fuel and fire but now I'm lost.

EinST

Welcome to the forum. It sounds like you ran down the battery. When you say "it won't even start," do you mean it won't crank?