Hi all, in the past my truck has had idling issues and has never allowed me to go through fast food drive throughs because of it. Well, a week ago I replaced the o2 sensor hoping it would solve my problems. Seemed to work for a little bit, but now the problem is back and worse than before. I was in an extra long drive through line, and it started spitting and sputtering terribly. Eventually it just stalled. It started back up but I couldn't get it going over 20 mph it was so bad. I turned it off hoping it would cool down and try again, well now it won't start. I don't hear the fuel pump turning on when turning the key, so I will assume thats why it won't start anymore. But I have no clue as to why its misfiring so badly. My mechanic is out of town for the next two weeks and plus I just got out out of the shop spending $2000 on a new rear end and new everything brake related. So I really don't want to have to take it to another shop and spend more $$. I just ordered a new fuel pump off ebay 5 minutes ago. My insurance is towing it home for free tomorrow. Any guidance on the misfiring stuff would be super helpful. Thanks!!

 

Before you drop the tank and replace the fuel pump, check the fuse and relay. The fuse is either blown or not. However, I had an '01 that was a problem child for the previous owner and the fuel pump relay was going out. I swapped it with the a/c relay (same art) and the problem went away. Bought a new relay and swapped them back and no more idle or odd noises from the pump area.

 

I agree check the fuse and relay. If you find they are good an the fuel pump is bad (Delphi or Denso only!!!) Your misfires could have been from bad fuel pressure.

 

I swapped the fuse out for another last night and that didn't help. Is there both a fuse and a relay? The 40 amp fuse was the only fuel pump related fuse I could find. Sorry if I'm missing something, I'm a noob.

 

Yes, there is a junction block under the hood and the relays will be labeled. Swap the a/c with the fuel pump relay and see what happens. You can always roll the window down but if the truck won't run, you're stuck. The inside of the cover will tell what is which.