97 stumble and fuel leak

[97powerstrokecclb]

Hey guys I'm having a problem with my 97 f350 powerstoke. Truck is stock besides an intake and exhaust, has 168,000 miles on it. This truck has always ran well since I have had it. Recently I have developed a stumble/hesitation when driving at lower rpm's. The truck is a 5 speed and it seems like when I go through the gears I get a stumble around 1500 rpm and it feels a little sluggish. When I get to around 2000 rpm it takes off and has more power. When I say stumble it feels like a hesitation or like the truck is jerking. I also changed the hoses on the fuel bowl to the fuel pump about a month ago and while troubleshooting this current issue noticed that there is a fuel leak in the valley. I haven't taken it back apart yet but the leak might be a clamp on one of the new hoses i hope. I put a gauge on the fuel bowl schrader valve and I have 60*psi*at idle so I don't think the fuel pump is suspect. Also the fuel pump looks pretty clean so I am not sure how old it is. My question is could the leak in the valley be letting air into the system and this is causing the stumble/hesitation I feel? Or is it possible I just got some bad diesel that is causing this? Is there anything else I should look at? Just for the heck of it I buzz tested the injectors and scanned for codes. Injectors all sounded even and came back with no codes. I hope to eventually go to efuel, but that will after tax returns. I just need to fix this until then.

 

[JCart]

So the fuel filter is clean yes and no codes came up? I'd unplug the wiring harness plug to MAP sensor and see if she runs better. If it does you may need a new one, should have thrown a code I think though. You might also clean the fuel return screen inside fuel bowl drivers side, take out the f filter. Use Q tips and flash lite and small mirror to get at the small screen, it's about a 1/3 way down bowl inside. When clean you should clearly see SS screen. Dip the Q tips in diesel, if not done before it will take a bunch to get the Keerap off the screen. And finally any up pipe exhaust leaks or leaks at the head to exhaust manifold interface, be sure to check drivers side at the rear to ensure manifold exhaust bolts are in good shape. The bolt heads some times can pop off this is not uncommon and then the manifold to head interface will leak. Look from the underneath side with flash lite to see if there is any black carbon on the head to manifold area and also behind turbo for leaking up pipes.

Cheers

jrc