Engine/Transmission (1994 - 1998) Somthing burning!

[RKrogh]

I have been reading the TDR site and learning great stuff about our trucks for a long time, but never had an occasion to write. Now I need help! Over the holiday, I drove to Eastern Washington where the temperature was in the mid 30's. One morning I plugged in the block heater about an hour and a half prior to start up. When I started up, the engine ran for about 15 seconds and then white smoke came up from the left side of the engine. I shut it down, and noticed that the smoke was coming from the area behind the fuel filter and above the lift pump. It dissipated quickly so I started it again to help locate the problem. It ran for about a minute before smoking again. It had a strange smell but not like fuel. The next day I drove it to the dealer in town without any smoke. Of course, it would not smoke for the dealer and he could not find anything burnt or malfunctioning. I drove it 300 miles home without any problems and no more smoke. Has anyone had this occur or any helpful hints on what to check? There must be something wrong somewhere!

 

[Jeff H]

Check the erea around the fuel pre heater. My thermo sensor burned up to a crisp. It stunk like wires burning. The preheater comes on when the temps get down to 40 degrees.

 

[chrleb1]

I've seen a couple of the connectors burn at the fuel heater. I'm not quite sure why they do it, but I think that the insulation for the heater wires get damaged and then it shorts... So check on that down there..... its just an idea.

 

[RKrogh]

Thanks for the response. Do you know if the fuel heater or the sensor is part of the lift pump on the 12 v CTD?

 

[Joseph Donnelly]

The fuel preheater has a filter screen and bowl on the bottom of it (check to see if it is getting plugged by threading the bowl off). This assembly is mounted to a bracket that goes between the lift pump and block. The assembly is to the front of the engine adjacent to the lift pump.