Jwald

Hello. My G20 with a 5.0 and 135k quit about a year ago. The truck started and ran fine until one day, it didn't. I was running errands and after a stop it just wouldn't start. It cranked, but it didn't start. I towed it home, let it sit, and 2 days later it fired right up. A couple hours later it wouldn't start again. Thinking fuel pump, I checked fuel flow, it was fine. Thinking cap and rotor, I replaced both. I checked spark at the coil, cap, and plugs. All was fine but no start. Out of frustration, I let the truck sit. A couple of days ago, it was suggested that it might be the spark control module. I put a charger on the battery to see if it would hold a charge for cranking, hit the key, and the damned truck fired up immediately. It ran a little rough, but it fired right up. I let it run for a few minutes and shut it off. In anticipation of a re-start, I gave it a couple gallons of fresh fuel and some Heet. 1 hour later it wouldn't start again. It tried, but wouldn't quite catch. 20 minutes ago I turned the key and it started and ran as well as it ever did. Service engine light is on as well, but the truck is no longer licensed and I have no code reader. Does anyone have any idea what the problem might be? Thanks in advance for your help.

canucklehead

When it does not start.....do you hear the fuel pump run a few seconds before you turn it over? When the fuel pump is working the volume and pressure will be fine, but when they start to go, they just don't run at all.
If you don't hear the pump run to prime....hit the underside of the gas tank with something and jar the pump. It should start and then its replace pump time.....filter too.

Jwald

Thanks. It is getting fuel even on a no start. I noticed something new also. When I started it this morning it ran great. When I shut it off, but left the key *on*, and slightly pressed the gas pedal, I got some kind of electric noise coming from the engine area; every time I did it. I just went out and started it again, but it ran rough, almost to the point of blubbering and dying. I no longer had a service light either. When I shut it off and tried the *key on pedal touch thing*, the earlier noise was gone. In addition, the outside air was heavy with *rich* exhaust fumes. This thing is all over the place.

Jwald

Update: The noise is a buzz, and the buzz is from the TBI. When pushing the pedal it is activating the injectors and spraying gas into the intake. I shut it off and tried it again; it doesn't do it. Got a match?

canucklehead

Bad injectors letting too much fuel in? Try unplugging the secondary, to lean out the van at startup. Just guessing. Not had this issue with my 95 I used to have.....