My 99 E350 Powerstroke Van has about 188K miles on it and it recently started running rough. The Service Engine Soon light would come on while it was doing it. It felt like it was missing on one cylinder. Then when it warmed up, it went away. Now it's doing it worse and it doesn't go away. The van will do about 0-25mph in 2 min. It's got to be running on 6 or less cylinders now. I limped it over to Autozone to run the codes and they said it was clear, no codes. I showed him the Service Engine Soon light but he insisted that it was clear.
I ran some Diesel Kleen additive through it when it first started doint it and it's drank about 1/4 of a tank of that stuff.

Any ideas?

 

Some of the Code readers at Autozone do not have the expanded codes which are needed for the Powerstroke engines. That is why it may have come up clean. Have you changed your fuel filter and air filters lately? I would give a bit more info on what you have done lately to your van (oil changes, CPS changed out, etc) and some of the people here will get you back up and running in no time. I use DK in every tank these days due to the new low sulphur diesel coming out.

 

If you have a SES light, you have stored codes, period. Either your friendly Autozone clerk doesn't have a clue (very strong possibility) or their reader can't pull the Powerstroke codes.
You will have to find someone that can pull the codes to make the diagnosis without just throwing parts at it.

 

Easy test. Pull the plugs for the wiring harnesses at the valve covers and check your injectors for continuity. If you look in the thread at the top of the page for the official glow plug thread, there's info on which pins are which, but, basically, check continuity (resistance) from the 4 smaller pins toward the center to the very center pin. There are 5 smaller pins in there, the very center one is the common ground for the injectors, and the 2 on either side are for each individual injector. Betcha got at least one that reads open.

 

Thanks for your replys. Sounds like I need to take it to the stealership to get the codes read. (last time they charged my $80 to check the codes).

Meanwhile, I pulled the injector harness plugs and put an ohmeter on the injector leads. They are all open. I used a bolt on the head for a ground. Did I do it wrong? The two larger leads on each side have resistance and the center one is the ground and the two on each side of the center one are the injectors, right?

I had overextended the oil last oil change but just changed it last week. It got a new fuel filter about 10K miles ago along with a cam position sensor. The engine has 188K miles and other than a few cam position sensors and oil line o-rings it's been trouble free.

 

Yikes! I just tried unplugging the drivers side injector harness plug and starting it. It starts and runs the same. If it do that to the passenger side, it doesn't start at all. That tells me that it's currently running on only the passenger side cylinders.

 

Well, you're starting to figure something out! You did do it wrong, you take resistance from the 2 pins to either side of the center pin (4 pins total, for 4 injectors per side) to the center pin, which is a common ground for all 4 injectors. The injectors work off about 130 volts DC, so they require their own ground. The lager pins near the end of the connector are for the glow plugs, those are 12v and ground through the block, so you should have gotten a reading on those.

If you have an electrical problem under the valve covers, the only thing the code is going to tell you is what you can tell yourself by checking continuity at the injectors.

If it ran exactly the same pulling one whole connector, I'm guessing the pass-thru in the valve cover is shot, but while you have the valve cover off go ahead and replace both the valve cover gasket and the wiring harness underneath. Wouldn't want to do one just to have the other go bad a week later!

If you need any more information, just ask! I went throught the same thing on my old 2000, albeit on only one injector. Tricky part of mine was that when you removed the valve cover and fired the engine, everything would work fine. Only when the valve cover was tightened would it act up. I believe both the valve cover gasket and harness was $65 from my international dealer.

Take your time here and you can save yourself a ton of $$$, just takes a bit of patience!

ON EDIT: With as many miles as your has, it would be a good time to replace the glow plugs as well. If you end up having to remove the valve cover you're 95% of the way to replacing them anyway. Next winter your engine will love you!

 

Thanks Rancha,

I'll pull the valve cover and start shopping for harnesses, gaskets, and glow plugs.

Dan

 

Is there a way to fix or rebuild the injector harness or will I have to just replace it? What normally is the problem with these things?


Dan

 

I wouldn't bother with trying to fix it... With the environment they live in, replacement would be a much better option.

When they get old, and oil soaked, they just conk out. Some people have pushrods runholes through them, some people have wire separation in the jacket, plugs that deform, broken connections, you name it!

 

mine was just the connector under the valve cover. $10 part at dealer. i say about 2 hrs to fix. never another problem.

 

Tonight I pulled the valve cover (not easy in a van) and checked continuity of the valve cover gasket connector (good) and then the continuity of each wire in the harness (also good). I figured that the ground must be bad. I put it back together and while doing so, found a wire that was worn through and I fixed that. It was not in the injector harness so I don't know if it was related.
I fired up the van and it runs good. So it was either my numerous prayers that God would heal my van, or just cleaning the carbon off the harness or that bare wire that I'm not sure what it goes to which I wrapped. Either way, I'm grateful.

Thanks for all your help. Without your advice, I would have just taken it to the dealership and paid hundreds of dollars for a fix.

 

Hmmm... May just have been junk in the plug, or maybe a plug that wasn't seated correctly... Now you know what to look for when one decides to run south on you!

 

I have a 1999 7.3 pickup and have the same problem. I took it to ford and the mechanic said it was the driver side harness. I only paid for the analysis but when I drove home all was well(no ses light). A month later it happened again just like the first time so I went to the dealer and paid about $80 each for the valve cover gasket and harness, installed them but she still runs as bad as ever! She is back at ford now but they can't get to it till next week. any ideas?