BigWheelie
Junior Member
- Joined
- Feb 11, 2024
- Posts
- 4
- Reaction score
- 2
- Location
- Yuma, AZ
- First Name
- Brennen
- Truck Year
- 1987
- Truck Model
- R30/C30
- Engine Size
- 454 TBI
Sorry this might be long and complicated and i might be missing some things but i noticed this is a common issue with these TBI models and mine seems to be different then all the common resolutions.
1987 Chevy R30 454 TBI 75k mi
I bought the truck not too long ago and after redoing the entire brake system and ran flawlessly. Clean steady idle, no vibrations, no misfires etc. Was an old mans truck with handicap plates and everything I've disassembled has been super clean. The truck came with one tank installed and the other in the bed. For some reason, one day my son accidentally flipped the tank selector switch to the driver side tank (not installed) and it was getting a CEL/SES light regardless if i cleared codes or switched to the correct tank. I ended up running a jumper cable to the tank selector connector to always run the passenger side tank (installed). From then the truck had worked for miles with no changes to any electrical components. One day we took it to the park and it died in the parking lot. One thing i immediately noticed was the jumper wires were hot and slightly smoking. I pulled the air cleaner and started cranking the motor and saw that i was getting no fuel. I looked for anything obvious initially but couldn't find anything until i checked the fuse box. I noticed i blew/melted the ECMB 10amp fuse. So i replaced it with spares i kept in the truck and the injectors still wouldn't fire.
When the truck was towed back to the house i started looking for frayed wires. I fixed plenty that seemed to be unrelated to the issue. I did find one wire that was hanging by a thread i thought for sure would fix the issue. It was the 2 wire connection that goes directly from the pump that was rubbing on the drivers side firewall. When i fixed that i still didn't get any fuel. I tested the injector pods with the 9 volt battery trick to see if they would engage and they did. I tested voltage to the ecmb fuse, injector harness and fuel relay which were good. I replaced the fuel relay anyways because the plastic slide on mount was broken and it was cheap. I cleaned every ground point and connector i could find as well as the power wires at the top of the firewall. I also got a new fuel tank selector switch. At this point i decided to drop the tank and check for signs of damage. BTW this whole time i could not hear the pump priming. With the tank half dropped, i disconnected the fuel lines and left the ground and electrical connections attached to see if the pump would push out anything at all. The pump did not push any fuel. So at this point i pulled the pump to bench test it. I supplied a 12v source to the pump outside the truck and it ran no problem.
Upon more research i noticed that the ICM seemed to be common with no fuel TBI issues. I installed one yesterday with the thermal paste and all. I reinstalled the tank and this time i cleaned the pump ground to frame to bare metal. I was still not getting any fuel however the injector pods would "drip" a little bit.
I am in the process of installing the other tank at the moment with a new pump. I have no clue what else to try and i don't trust professional help with older vehicles as I've never had a good experience with mechanics these days.
1987 Chevy R30 454 TBI 75k mi
I bought the truck not too long ago and after redoing the entire brake system and ran flawlessly. Clean steady idle, no vibrations, no misfires etc. Was an old mans truck with handicap plates and everything I've disassembled has been super clean. The truck came with one tank installed and the other in the bed. For some reason, one day my son accidentally flipped the tank selector switch to the driver side tank (not installed) and it was getting a CEL/SES light regardless if i cleared codes or switched to the correct tank. I ended up running a jumper cable to the tank selector connector to always run the passenger side tank (installed). From then the truck had worked for miles with no changes to any electrical components. One day we took it to the park and it died in the parking lot. One thing i immediately noticed was the jumper wires were hot and slightly smoking. I pulled the air cleaner and started cranking the motor and saw that i was getting no fuel. I looked for anything obvious initially but couldn't find anything until i checked the fuse box. I noticed i blew/melted the ECMB 10amp fuse. So i replaced it with spares i kept in the truck and the injectors still wouldn't fire.
When the truck was towed back to the house i started looking for frayed wires. I fixed plenty that seemed to be unrelated to the issue. I did find one wire that was hanging by a thread i thought for sure would fix the issue. It was the 2 wire connection that goes directly from the pump that was rubbing on the drivers side firewall. When i fixed that i still didn't get any fuel. I tested the injector pods with the 9 volt battery trick to see if they would engage and they did. I tested voltage to the ecmb fuse, injector harness and fuel relay which were good. I replaced the fuel relay anyways because the plastic slide on mount was broken and it was cheap. I cleaned every ground point and connector i could find as well as the power wires at the top of the firewall. I also got a new fuel tank selector switch. At this point i decided to drop the tank and check for signs of damage. BTW this whole time i could not hear the pump priming. With the tank half dropped, i disconnected the fuel lines and left the ground and electrical connections attached to see if the pump would push out anything at all. The pump did not push any fuel. So at this point i pulled the pump to bench test it. I supplied a 12v source to the pump outside the truck and it ran no problem.
Upon more research i noticed that the ICM seemed to be common with no fuel TBI issues. I installed one yesterday with the thermal paste and all. I reinstalled the tank and this time i cleaned the pump ground to frame to bare metal. I was still not getting any fuel however the injector pods would "drip" a little bit.
I am in the process of installing the other tank at the moment with a new pump. I have no clue what else to try and i don't trust professional help with older vehicles as I've never had a good experience with mechanics these days.
