th3 cavalry

I have a speed density 300 I6. It has some fuel or ignition issues. Let me explain.

I got the truck during the winter. There was a hesitation and slight bucking once it started getting warm under part throttle but run fine when i floored it. Sometimes it ran fine at temp but more of the time it had the hesitation and bucking. Here in KY we had a few very cold days. When driving for the first time in the morning to work, the colder it was outside the longer it ran fine until the temp needle started moving then the CEL would come on for EGR valve(I have the vacuum hose unplugged and capped right now.) I drove like that for a while and added a decent audio system in the truck. It was enough to make the lights dim and when the lights dimmed you could feel the truck "cut out." So I thought it was a grounding issue possibly. I upgraded to a 130 amp alternator and went to all 0 gauge wiring but issue was still present.

Now its a lot worse. Its very hard to start the truck sometimes and it does die on me. It acts like it is starving for fuel. I give it gas and it just stumbles all over itself. It will then run fine for a minute then just start stumbling again. No matter how much I press the gas pedal it doesn't go anywhere. It will backfire in the intake sometimes. The exhaust smells like gas but never backfired through the exhaust. I'm desperately needing to get this truck running.

I have a new fuel pump im installing tonight or tomorrow in the rear tank since its bad. (I want to yank the front tank and put a air tank in its spot)

memoniz

What year is your truck?

I find when this happens that you are describing, the timing is usually off. Have you messed with the distributor lately? I left my distributor bolt somewhat loose once and after a couple of weeks my timing was so off that I couldn't get up to 15 mph and my engine was super overheating in a matter of seconds. Retimed it and everything was fine. Bad timing can cause backfire but so can a EGR. Try running codes, it could only help.

th3 cavalry

So my truck is acting a little better, however still bucking, hesitating, and a noticeable lack of power. What I have done if checked my PCM and the capacitors are not leaking, tested the ICM, and replaced the distributor. There are no wiring issue from what I see, and no vacuum leaks. There are two plugs that are not plugged into anything and I go over them in video number 1. Here are two videos. #1 is with EGR vacuum plugged in and #2 is with it unplugged and capped off.

I don’t think its fuel pressure because its in and out. More often then not its acting up but it does have a minute or two where it works fine. I do have a multimeter and I do know how to use it so if any voltages need to be tested I am capable of doing it.

#1

#2

Ford 4x4

Did I hear right that you set the timing to 2???? If so it might help to set it to 10 degrees before top dead center. (I think thats stock)

th3 cavalry

no, 10 degrees

Ford 4x4

oh okay I though I heard you say 2. Nevermind

memoniz

We're you able to pull codes? Also did you do any of that tank work? I notice the fuel level was low and there might be junk in the tank. Also I would try an additive to clean the full system, like Sea Foam.

If the fuel filter hasn't been changed in a while, you might want to do that also.

th3 cavalry

Ready for a loop?

I've been running off the front tank since I got the truck. The rear tank would cause the truck to die or BARLEY run at all. I was driving and shut the truck off and when I went to start it and it wouldn't. You could hear it trying to fire but wouldn't. I decided to swap the 4 relays under the hood and I kinda abused the fuel tank selector switch. Still wouldn't fire up. SO I then switched it over to the rear tank and it fired right up but won't run on the front tank now. Its acting like its not getting enough fuel... Driveability is better then it has been, I just have to feather the pedal. I city driving is more pretty then highway driving...

I stunt motorcycles so I'm going to be putting the rear on airbags to assist with loading the truck. I'm going to pull the front tank out and put a air tank and compressor in its place. So the fuel selector switch will be getting removed soon so if I can go ahead and bypass the switch to run off the rear tank all the time I will go ahead and do that to get rid of a possible cause...


Also truck does NOT have a check engine light and NO stored codes since I have hooked everything I can up. When I first got the truck a few months ago codes would store so I don't think its PCM. Especially since I checked the caps and I'm a computer science major so I know what to look for with bad circuit boards...

th3 cavalry

So now it seems like I'm tracking down a fuel issue. I don't think its the pumps themselves but something within the wiring.


I'm about to pull my bed off and I want to start getting ready to pull the front tank off... Can I just plug up all the hoses that go to the front tank? What about the wiring? I do want to get rid of the fuel tank selector switch and have just a simple single tank setup...

dutchiii

i just have my lines plugged on my front tank. I don't think it has caused any negative effects so far so id say you could probably do it. just be sure that you get the return line plugged completely because i ended up dropping half of my tank dripping fuel down the highway...