Engine/Transmission (1994 - 1998) Run On Problem

[proskeeterman]

On my way home from vacation, pulled into gas station to re-fuel. Turned off the ignition switch, but motor kept on running. Turned switch again and it stopped. This has happened a couple of times since (mostly after long periods on the highway), but everytime so far I have just turned the ignition switch back on then off and the motor quits. Is this a fuel relay problem or is this the ignition switch needing to be replaced? On a different note my headlight is starting to malfunction. I have a replacement switch ready to put in but it's my understanding the dash has to be removed to replace the switch. Is this the case? My thanks to all that respond, you guys are amazing.

 

[ata]

The first thing I would do is when the engine keeps running. I would pop the hood get out and pull down on the fuel shut down linkage coming out of the solenoid on the pump. If it pulls down and stops the engine I would take the plunger out and clean it and put some light oil on it and the linkage. If you can't pull it down then I would say you have an ignition switch problem. I don't think the relay would hang up. You could also check and see if you have power to the relay from the switch in the off position when the engine keeps running. If you don't then I would say the relay is hanging up.

 

[snappy]

Dash does not have to come out to change headlight switch. Remove screws holding ashtray and cupholders, unsnap cluster trim and disconnect cig lighter. Undo the screws (3) that hold headlight switch. Disconnect the batteries first. Some headlight switches has a ground wire. Inspect connector for burnt wires.

 

[LandShark]

My bet is worn out starter contacts. A common problem on 2nd gen trucks. The contacts stick and set up a feed back loop thru the starter shutdown relay and keeps the motor running running with the key off. Rebuild with heavy duty contacts; an easy job.

After you fix the headlight switch, get a relay kit for the headlights. This takes the load off the switch and also gives you brighter lights. Another common problem for 2nd gens.

 

[Missouri Mule]

Mine has stuck before several times because of the starter solenoid contacts/plunger sticking but the starter also keeps running if this happens. (This also usually happens when you first start the engine. )



I betting it is just the rod being dirty spay it down with wd-40 and move it up and down afew times see if that helps. ( That is what I have done when mine has stuck on me. Not caused by solenoid contacts/plunger). It could be also your ignition switch. The ignition switch powers the hold up coil on the fuel shut off solenoid.

 

[DieselDoghouse]

Like Missouri Mule said - I thought if starter contacts stick the starter tries to stay 'hot'. I would suspect binding in the fuel solenoid slug—and that usually means the rubber is cracked and admitting dirt. pull the solenoid, clean and lube the parts, and replace the boot - available through Geno's or Fostertruck as examples.