RJZBYD

Driving to work the other day, got stuck in traffic (stop and go) looked out the back and the truck was blowing a lot of White smoke and running rough. Pulled over at the next exit opened the hood nothing out of the ordinary, turned around to go home and grab other truck, smoke cleared up and truck started running fine. Injector problem? Lift pump? Injector pump? That night I changed the fuel filter, and added fuel system lube. It happened the next evening but cleared up again. Any ideas? 1996 with 190,000 miles

marine4life

you can rule out your injectors by checking each one. turn the engine on and let it run, loosen the #1 injector nut until you can see fuel coming out, you should hear a tone change in the engine, if you hear it, tighten it back down, and move on to the next injector, move back all the way to #6 checking each one, if you don't hear a change when you loosen one, then you have a bad injector. your timing might be another problem, have you ever checked it?, i doubt it is the lift pump, they rarely fail, you might want to replace the overflow valve, they fail every so often , they regulate the fuel pressure. but my guess would be timing, retarded timing cause excessive white smoke and loss of power. im sure someone else will chime in with other suggestions.

Willy91

I agree that it might be timing. How does it rev. Is it real smooth, or does it take a lot of effort to rev it high.

TxDiesel007

Sounds like the timing

has slipped, since you have changed your fuel filter already i would rule that out as a possibility.....

Rick

inline6359

i went throught the same problem but mine smoked white wen i dead reved it and had a flat spot on the top end. anyways all it was was a bad fuel filter that sucked my fuel pressure down to zero. just a thought.

Rick

RJZBYD

Thanks for the replies!!!!!
Drove the truck today put on 150 miles no problems at all. If the timing has changed i should have the problem all the time right? Could an injector be clogging? Maybe I will try the overflow valve, first. This has been a great truck so far. I have done nothing but maintenance and upgraded what I wanted, other than that water pump at 180,000. Fords that I owned needed a water pump every 90k. Again thanks for the help.

Hemi Cat

I would put a fuel pressure guage on it first. Your problem is intermittent, timing is constant. The overflow valve has a spring and check valve that could cause problems, the lift pump has 3 check valves that can cause problems, you could have air leaks in the fuel lines (and hard starting with smoke), the water seperator/fuel heater has a filter screen that few people service that will clog and cause fuel starving problems, injectors could stick and cause this too but it should knock real loud like a rod knock.