Engine/Transmission (1994 - 1998) Fuel Shutoff Solenoid Issues

[BlameCandida]

For the past month my fuel shutoff solenoid has been unreliable, so I have to manually compress the spring about half the times I start the truck. I checked the voltage at the harness, and it was okay. Yesterday I finally had a block of free time, so I removed the solenoid assembly and gave it a thorough cleaning. There was plenty of crud on the piston from the disintegrated rubber boot and a dusting of rust on the spring. I dried everything off, and reassembled and reinstalled the solenoid. That afternoon and evening the truck started fine everytime, but this morning it is back to not working. The solenoid stays in place just fine once it is up.



What are my options here? Should I go for a new assembly from Larry B/ Geno's Garage, try to service the original solenoid again, or install a manual cable to the cab?

 

[budnate]

I picked one up from Larry B, super quality piece, priced fair and I had in like 2 days after I called him, hard to beat that, and the truck ran better than it ever had after the install.



B.

 

[BlameCandida]

I keep hearing about this blue fusible link that is supposed to protect the fuel shutoff solenoid, but I'm not seeing it. I attached some pictures of my battery and relays. I also have this mystery wire coming from the relay box. Is this supposed to go somewhere, or did a previous owner use it for something different?



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[MLee]

This sounds like an electrical issue. You cleaned the solenoid, worked fine then not working. Put some dielectric grease on the pins, in the connecters for continuity if it does not improve, get a relay, the big one on the master cylinder side of the two. It might be weak.

 

[MLee]

On Your in bed trailer connecter, I recommend putting a Relay in the hot line and get away from the FUSE. This way it will reset if you have a short. And might keep you out of trouble some day.

 

[BlameCandida]

I bought the truck from a Minnesota snowbird who pulled a fifth-wheel with it. I never actually use the in-bed trailer connection, so I might just take those out. There were quite a few things on the truck that were wired in incorrectly: lights under the frame, brake controller, etc. That's why I was wondering about that mystery wire in the third photo. I don't know if it's supposed to go to something still on the truck, or if the owner ran it to some accessory he later removed.

I'm not sure which relay you're referring to for the fuel solenoid. Is this a relay in the big fusebox, or somewhere outside of it?

 

[Missouri Mule]

There are two relays hanging on the cowl above firewall/intake manifold the larger one is the fuel shutoff solenoid realy. The relay when going bad will operate intermittently.



Depending on the year of the truck there should be a blue wire coming off the battery hooking up to a fusible link,later years have fuse( I believe in the PDC). It seems to me 94 to 97 have the fusible link and in 98 they ran the power to the FSS relay thru a fuse.



If if the fuslible link or fuse in bad it won't work at all (Pull up coil on solenoid).

 

[Joe G.]

Any time you post a question you need to tell us what year your truck is. There are differences between the years. Many times we need to know if you have an automatic or manual transmission or if the truck is a 4X2 or 4X4. Most people do that with a signature.

 

[MLee]

Your mystery wire might have gone to a light in a topper when the trailer was not in use during the winter, he put a topper or cover on the bed. It sounds like the brake control is still there. Or, I was thinking that the mystery wire might have been the hot wire for the brake control.