Help: I have a 1993 chevy c60 with a 366 engine. It has been a good truck and maintained good. It was sitting ideling the other day, I went inside the shop and I heard it die. It wouldnt restart. I could'nt hear the fuel pumps (dual tanks ) cyclling or humming, so I just figured it was a fuel realay or fuse. After taking the glove box out and finally figureing out which relay was the fuel relay, it was ok. Found another relay, under left door, under step, Has 4 wires. One to each tank, (fuel pump) one is hot when key is on. I assume the other is hot when cranking, provided power to each wire to tank and fuel pumps ran, after pulling my hair out trying to figure it out decided to check for spark. No spark. It has throttle body injection (I think they used this only one or two years) No spray when cranking, so I went ahead and replaced the module. Still no spark. I am going to try and check coil ( will probably just get a juse one from the junk yard, for testing) and I checked the pick up coil. Had a circuit and no ground, showed contunity. I guess my question is that if the computer is bad will it keep it from having spark and preventing the fuel pump from running. (hope that is not bad.) Or if there is a problem in distributor, will that prevent fuel pumps from cycleing. I checked all fuses and power wires. I live in a area thas really doesnt have any experienced heavy duty truck repair places, and to have it towed to nearest Chevy HD garage is quite a distance. Is there any web sites that I can get help or information on. Or a diganosis check list to help eliminating some things. For some reason I have it in my head now that it is distributor related, (no spark). Seems like on some vehicles if you have no spark then it wont fire the fuel system, (fuel pump and injector) These problems are not covered in a HD truck manuel. Probably have to have the factory "electronic controls manuel". Any help appreciated.
You should see if you can draw codes from it as it is computerized. See what it comes up as. If any one piece of the system screws up nothing works. On those Chevs with a distributor the module under the distributor had a habit of going. When you change it put some dielectric grease on the bottom of it to keep it from shorting against the housing. Also computers are not that expensive any more as there are rebuilt units out there now. But best to pull codes first that should lead you in the right direction.
Thats why I just went ahead and replaced the module as they are noted for going bad. I did put the dielectric grease under it. It is a small dump truck and I use it to make extra money. It has 130 K miles. I bought it about 8 years ago from a chev truck dealer. They sold it to me as having a bad valve or something as they couldnt get it to run right. I tuned it up but still never ran right. Would burn up plug wires, burn distributor caps, rotors. Just kept replaceing those items. Took it to a garage and they couldnt get it fixed right either. No power, ran rich, just ran it this way for 3 years as no one could fix it. It was like haveing a bad pair of underwear rubbing you raw and you takeing them off and you cant find the bur. So you live with it. One day I had a old coil off another truck. (had coil on truck checked before.) ran like a new truck, quit burning plug wires, rotors and caps. Been ok for about 4 or 5 years now. I would take it to a chev. truck dealer, but none in my area that knows any thing about them. Plenty of HD truck shops, that know all about diesels but medium gas truck dealers are hard to find that has any one who knows anything. Going to try and draw a code from it. Thinking it is a ignition problem rather than a fuel. I guess if it wont fire then it wont send a signal to actuate the fuel pump. I guess thats what threw me off and got me started on the wrong track as the truck just shut down, no miss or any thing and I didnt hear the fuel pumps running or fuel spray so figured it was a fuel related problem, till I finally checked the spark and had none. Some one told me that a bad computer on that model of truck wont keep it from fireing, just wont run. So will recheck distributor, (already replaced module) and maybe get a used coil to throw on it to see what happens. Just trying to pick every one brain to get it running.