I recently bought a 1999 F350 with 365,000 miles on the ticker....
I have had no troubles except for some leaky up-pipes so far. The truck now has 369,000 miles on it and I just developed a serious misfire, rough idle, no power condition, white smoke that smells like wet fuel.

Last night driving home, right after filling up the tank, I had good power and started to hear what sounded like a louder exhaust leak. A soon as I got home and parked the truck the idle went rough. After restarting the truck the idle got rougher and has no power.

I will be testing the resistance on the valve cover plugs tonight to see if their is a bad injector or loose plug. Changing the CPS, guess I will be doing the 50 cent mod whenever I pull the valve covers off.

What other gremlins should I be searching for?

 

It sounds like you have a good plan.. do you get a check engine light ? If so, you have codes stores for sure.. Re- torque everything under the covers.. see:
https://www.ford-trucks.com/forums/8...ck-shakes.html
Check your engine valley for signs of fuel leaks, etc..
Pull your ICP electrical plug and check for oil leaks..
Check you IPR for loose nut..

 

Not to say that it can't be the case, but save yourself some time.

It may be fuel related......

Open connections in the valve cover harness WILL NOT cause an injector to dump fuel (which would cause a white smoke condition if there was enough of it...just a little causes a knock and puffs of black smoke). You're getting fuel (as evidenced by the white smoke that smells like raw fuel. If you have an open in any injector circuit, you WILL NOT get fuel in the cylinder). You've likely got a mechanical problem of some sort like low compression caused by broken rocker arm(s), bent pushrod(s), hole in piston, etc. or you've got an injector hold down that's loosened up and allowed the injector to become unseated in it's sleeve and it's allowing fuel to dump directly into the cylinder.......

Time to check for blowby and non-moving valves. That would be my first move if a fuel API rating proves that you have diesel fuel in your tank.


Just a thought.

 

My first thought on this would be a bad injector! The injector can stay stuck open and dump fuel in the cylinder. What I would do is take the valve covers off plug your harness back in and start the truck. Once you have it on start unplugging your injectors one by one and see if your engine changes. For each injector if the engine changes or idles rougher then that injector is good. If the engine stays the same then that is your bad injector.

 

Well, there are no codes, no check engine light at all..... that is what scares me most.
I am already planning to destroke this truck within the year but just not yet.

I will be posting what I find tonight... Thanks for the help guys

 

I had this issue last year, but it was what I found the cost. I would check your compression on all cylinders. White smoke and raw diesel is what I had. After all of test request from friends on this site I found cylinder #7 had no compression. I went out a bought a gauge that would work for the truck and did the test. All cylinders at cold had 350psi #7 was 0..Hope this helps.

 

Well, I got 2.0 - 2.1 ohms on the glowplugs and 5.2 - 5.9 ohms on the injectors. Sounds like something more serious unfortunately. Oil level is good, hpop oil is good, hardly any blowby.
I guess my next step is to pull the covers? Look for valves not moving, injectors loose, Etc.

 

Well, I got 2.0 - 2.1 ohms on the glowplugs and 5.2 - 5.9 ohms on the injectors. Sounds like something more serious unfortunately. Oil level is good, hpop oil is good, hardly any blowby.
I guess my next step is to pull the covers? Look for valves not moving, injectors loose, Etc.

 

Chad, my truck did the same thing 4 days ago. Started running rough like on 4 cylinders.I kinda thought one bank of cylinders shut down. Didn't have enough power to pull its own shadow.

I was sure it was UVCH related. After pulling VC"s, one high ohm reading,and checking everything out. It turned out to be fuel related.
Installed new pump today and she fired right up. I would check first if it isn't fuel related.
Good luck

 

Grady, sounds like I should check the fuel pressure while I'm at it. After pulling the valve covers number 2 and number 4 cylinders are the culprits. When I unplug the injectors the idle does not change. All others make the idle worse. I'll torque everything down and try it again tomorrow. Could the injectors be the actual problem? How should I check the fuel pressure?

 

Yes the injectors can be the problem, I would get those checked or replaced. Let us know what else you find.

 

I will be testing compression on the truck tonight. Given that the two injectors need to be replaced, can I get away with just replacing those two injectors or will I end up replacing all of them?

Local guy said with his personal experience that after you change a couple the other injectors begin to fail.

 

just replace those two, if the others aren't giving you problems you should be fine.

 

I had #8 fail at 20K.. Ford replaced it.. the rest of them are still fine..

 

Its a toss up. If it was me I would replace all of them at the same time. I'm currently in the same state as you. I have 1 and 5 giving me trouble. I plan on getting the Stage 1 injectors from Clay at Riffraff diesel. You can just replace 1 or two. But I have see where once one or two go the others follow shortly after and it might be 5000 or it could be 30000 miles. If your in a money crunch Clay has reman stocks for I think $125 each.