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dmnall · 10-12-2002, 03:44 AM

When my truck Vapor Locked on me, it never ran rough but it would just cut out on me and Die!! When I had a problem w/ my ignition module in my HEI, when the module would get Hot and shut down, my engine would run rough because it was having a weak spark and then it would shut down.. After about 30 min - 1.5 hours, it would start up and run Rough for about 10 minuets then it would run fine untill the Module Heated Up and shut off again.. Talk about a PITA, I drove around for about a week thinking that it was Vapor Locking, then one night I drove out and it did the same thing and lucky enough I had my dad and a small screwdriver w/ me to check spark!! I replaced the Module the next day and never had a problem since!!

Also if you are sure it is Vapor Locking, then answer a couple of Questions for me. What kind of Fuel Pump are you Running ?? Are you Running Headers ?? If you are using a Mechanical Fuel Pump and Headers, Switch to an Electric Fuel Pump and put the Fuel Pump as close to your gas tank as Possible! If you are running an Electric Fuel Pump, do you have it installed in Engine Compartment ?? Well the solution is move electric fuel pump in the frame rails as close to the Gas Tank as possible.. Headers can really cause Vapor Lock, if you have mechanical fuel pump or electric fuel pump in the engine compartment!! Trust me on this subject because I burned 2 electric fuel pumps up because of the heat problem and I had my fuel pump in my engine compartment! (It took me 2 weeks before I learned to move my electric fuel pump underneath my cab in the frame rail.)My truck vapor locked every time I drove it to town untill I moved my fuel pump!!

10-12-2002, 03:44 AM	#2
dmnall Registered User Join Date: Apr 2001 Location: Goleta, CA Posts: 505	When my truck Vapor Locked on me, it never ran rough but it would just cut out on me and Die!! When I had a problem w/ my ignition module in my HEI, when the module would get Hot and shut down, my engine would run rough because it was having a weak spark and then it would shut down.. After about 30 min - 1.5 hours, it would start up and run Rough for about 10 minuets then it would run fine untill the Module Heated Up and shut off again.. Talk about a PITA, I drove around for about a week thinking that it was Vapor Locking, then one night I drove out and it did the same thing and lucky enough I had my dad and a small screwdriver w/ me to check spark!! I replaced the Module the next day and never had a problem since!! Also if you are sure it is Vapor Locking, then answer a couple of Questions for me. What kind of Fuel Pump are you Running ?? Are you Running Headers ?? If you are using a Mechanical Fuel Pump and Headers, Switch to an Electric Fuel Pump and put the Fuel Pump as close to your gas tank as Possible! If you are running an Electric Fuel Pump, do you have it installed in Engine Compartment ?? Well the solution is move electric fuel pump in the frame rails as close to the Gas Tank as possible.. Headers can really cause Vapor Lock, if you have mechanical fuel pump or electric fuel pump in the engine compartment!! Trust me on this subject because I burned 2 electric fuel pumps up because of the heat problem and I had my fuel pump in my engine compartment! (It took me 2 weeks before I learned to move my electric fuel pump underneath my cab in the frame rail.)My truck vapor locked every time I drove it to town untill I moved my fuel pump!! __________________ 1968 C10 Truck LWB Fleetside 1968 C10 Truck SWB Stepside 1994 K2500 Ext Cab Fleetside 2008 Honda Civic Si lease Last edited by dmnall; 10-12-2002 at 03:53 AM.