7.3 no start troubleshooting
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7.3 no start troubleshooting
Hello everybody. I really would appreciate some help with my truck.
I have a stock 1996 F350 dump with 213k. I bought this truck about 5 years ago with about 200k, and I've only changed the CPS, oil and filters up until 2 months ago. Since then, I've swapped a bunch of parts trying to solve a no-start problem. I don't have a scanner, so I'm reading everything I can and asking my buddies lots of questions. Here's the sequence of events.
I made two trips to a neighbor's farm to haul dirt with no issues. After loading my third load, the truck would only turn over but no coughing, sputtering etc. My buddy helped me drag it home and I replaced the CPS (Delphi) and the oil-soaked IPS (Motorcraft). No change.
I checked out the IPR and noticed the nut and spacer were gone and the solenoid was loose. I removed the fuel bowl and found the spacer but didn't find the nut. I installed a new IPR (Motorcraft) and new fuel lines and hose clamps. I was certain it was fixed. This time it started. I let it run for a few minutes and then went and dumped the load of dirt that was still in the truck. I drove about 200 yards, dumped the load and was cleaning out the bed when the RPMs started dropping slowly like their was fuel/air restriction. It died and wouldn't start but it would cough and splutter. I cleaned the fuel bowl and the screen to the FPR. No change. I inspected the external connectors to the UVC harness and they looked OK. I wiggled them and it made no difference.
I had no way to check fuel pressure, but I began to suspect the fuel pump. So I replaced my old one with with one from RockAuto (Carter). It started, but soon died out again.
I borrowed a good IDM and plugged it in. It started and idled fine but I noticed a fuel leak coming from the weep hole in the new pump so I got another pump from RockAuto and a used IDM from a junkyard. This time it starteed, and ran pretty good with just a little miss that I figured was air in the fuel system. I drove it down the road and after a few miles the miss was gone and the truck was running great. On the way back home I started smelling fuel and white smoke was blowing behind me so I knew I had a leak. My engine was absolutely soaked with fuel. Turned out it was the rotted rubber return line from the driver's side head to the FPR. The other side was dry-rotted as well so I replaced both.
Once again, i was certain it was fixed, but now it will fire but won't start. If I keep turning it over, it fires more quickly (the firing is closer to together and occassionally it will run roughly for 10 seconds or so and then die. Tonight I unplugged the IPS and tried again with no change. I did notice the stud on the glow plug relay that has constant voltage was smoking and the rubber insulation was cracked but it stopped after I cleaned it up and tightened it down. I did check with with the volt meter and confirmed the other stud that supplies voltage to the glow plugs was getting power when the key was on. The truck does not have a CEL on.
I'm thinking about pulling the IDM from my 2001 F250 and checking to see if the junkyard IDM failed, but it's a pain to get out, and I'm concerned that if there's something wrong with my UVC harnesses that fried my IDM I could also fry my 2001 IDM.
I've always planned on sending my injectors to Rosewood and replacing the glowplugs, harnesses, gaskets, connectors. Just have nver got around to it because the truck would run decent enough to work. Seems like it might be the time to do it.
What do you guys think?
Thanks!
John
I have a stock 1996 F350 dump with 213k. I bought this truck about 5 years ago with about 200k, and I've only changed the CPS, oil and filters up until 2 months ago. Since then, I've swapped a bunch of parts trying to solve a no-start problem. I don't have a scanner, so I'm reading everything I can and asking my buddies lots of questions. Here's the sequence of events.
I made two trips to a neighbor's farm to haul dirt with no issues. After loading my third load, the truck would only turn over but no coughing, sputtering etc. My buddy helped me drag it home and I replaced the CPS (Delphi) and the oil-soaked IPS (Motorcraft). No change.
I checked out the IPR and noticed the nut and spacer were gone and the solenoid was loose. I removed the fuel bowl and found the spacer but didn't find the nut. I installed a new IPR (Motorcraft) and new fuel lines and hose clamps. I was certain it was fixed. This time it started. I let it run for a few minutes and then went and dumped the load of dirt that was still in the truck. I drove about 200 yards, dumped the load and was cleaning out the bed when the RPMs started dropping slowly like their was fuel/air restriction. It died and wouldn't start but it would cough and splutter. I cleaned the fuel bowl and the screen to the FPR. No change. I inspected the external connectors to the UVC harness and they looked OK. I wiggled them and it made no difference.
I had no way to check fuel pressure, but I began to suspect the fuel pump. So I replaced my old one with with one from RockAuto (Carter). It started, but soon died out again.
I borrowed a good IDM and plugged it in. It started and idled fine but I noticed a fuel leak coming from the weep hole in the new pump so I got another pump from RockAuto and a used IDM from a junkyard. This time it starteed, and ran pretty good with just a little miss that I figured was air in the fuel system. I drove it down the road and after a few miles the miss was gone and the truck was running great. On the way back home I started smelling fuel and white smoke was blowing behind me so I knew I had a leak. My engine was absolutely soaked with fuel. Turned out it was the rotted rubber return line from the driver's side head to the FPR. The other side was dry-rotted as well so I replaced both.
Once again, i was certain it was fixed, but now it will fire but won't start. If I keep turning it over, it fires more quickly (the firing is closer to together and occassionally it will run roughly for 10 seconds or so and then die. Tonight I unplugged the IPS and tried again with no change. I did notice the stud on the glow plug relay that has constant voltage was smoking and the rubber insulation was cracked but it stopped after I cleaned it up and tightened it down. I did check with with the volt meter and confirmed the other stud that supplies voltage to the glow plugs was getting power when the key was on. The truck does not have a CEL on.
I'm thinking about pulling the IDM from my 2001 F250 and checking to see if the junkyard IDM failed, but it's a pain to get out, and I'm concerned that if there's something wrong with my UVC harnesses that fried my IDM I could also fry my 2001 IDM.
I've always planned on sending my injectors to Rosewood and replacing the glowplugs, harnesses, gaskets, connectors. Just have nver got around to it because the truck would run decent enough to work. Seems like it might be the time to do it.
What do you guys think?
Thanks!
John
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