Engine/Transmission (1994 - 1998) Fuel heater wiring issues

[MWyckoff]

I recently bought a '98 12V, and ever since had problems with it starting. I was looking at the wiring for the fuel heater the other day and found there were no wires going to the fuel heater relay. I traced all the wires coming from the fuel heater and can't find any that are disconnected. I was wondering if anyone knew the approximate location in the harness where these wires would come out so I can check to see if they have been choped.

 

[KYOUNG]

The fuel heater probably burnt up and they removed the fried wires... there was a recall on some years to fix wires... ..... my 98 had a burnt up fuel heater when i bought it and it was sucking air. i removed the fuel heater and truck has started and run fine ever since, it was 5 below zero yesterday when i went to work!!

 

[Bill Lins]

There was a recall on early '98's for MISSING fuel heater wiring- you might want to check with a dealer to see if yours is covered & if the recall had ever been done on your truck.

 

[SDrake]

Fuel heater would not affect starting in any way except when it is so cold that the fuel might gell.



You are probably getting air into the rubber hoses that connect the fuel intake and return lines at the rear of the engine to the metal hoses coming up from the firewall. The will leak air but not fuel. Will make the truck harder and harder to start as they leak more and more but may run fine otherwise.

 

[MWyckoff]

Thanks guys, I will look at these things.

 

[KWentling]

'98's no longer used the relay on the firewall and power came from the PDC instead. That was the wiring that they added in the recall. When mine started leaking air, the problem was at the fuel heater. If you unplug the harness and it's wet, you found the problem. I replaced all the rubber lines and the only one that was showing it's age was the one from the overflow to the steel line behind the filter. the ones from the frame looked like new once the covering was off. I did those before I discovered the leak at the fuel heater.



Kim