Ford Powerstroke Diesel Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
I posted this in the 7.3 Engine problems forum, but thought I would post it here too in case that was the wrong place.

My son's 96 7.3 PSD just started going crazy. It idles smooth for about 5 seconds after starting then it starts running very rough. It sounds like something clicks and the engine speeds up some and sounds like it's going to tear itself to pieces. You can shut it off and restart and it does the same thing, including the smooth idle for about 5 seconds.

Anyone got any ideas?? He has replaced the cam pos sensor with a new Ford part, the oil and filter has recently been changed, and the fuel filter is new.
 

·
BIG TRUCK, SMALL DRIVER
Joined
·
5,877 Posts
Have you pulled any codes?
 

·
Registered
Joined
·
7 Posts
Discussion Starter #4
pipelayer- Can't read codes, yet. Borrowing one from a friend.
I forgot to mention that the CEL comes on while it is running bad. You can speed up to ~1700 rpm and it smooths out, but you can't put a load on it or it goes rough again.
 

·
BIG TRUCK, SMALL DRIVER
Joined
·
5,877 Posts
let us know what codes you come up with.
 

·
Registered
Joined
·
5,534 Posts
hey, my truck did the same exact thing, it was the passanger side under valve cover wireling harness coming loose. i do have a 99 but sounds the same.
 

·
Registered
Joined
·
142 Posts
:agree:
the 1661 code for low voltage could very well be your under valve wiring harness which caused the other codes. My truck had the same problem a while back and I had a loose connection in the passenger side wiring. Those harnesses could be causing most of your problems. If you have to replace the undervalve wiring harness you might as well replace glow plugs while your in there.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #10
Thanks for the inputs!! It sounds like the under valve cover harnesses are a weak point. We'll pull the valve covers tomorrow and see what the harness looks like.
Are the harnesses expensive?
 

·
Registered
Joined
·
7 Posts
Discussion Starter #11
Problem is fixed...Thanks!!

cchase and gonstrokin you guys hit it right. It was the driver side front wiring connector. I was able to pull on the harness while it was running and make it run smooth. It has been running smooth since tehn, but we're going to replace the under-vc wiring, the vc gasket, and check out the wiring harness.

Thanks again.
 

·
Registered
Joined
·
1,395 Posts
good to hear that your running again.
 

·
Registered
Joined
·
521 Posts
1 - 14 of 14 Posts
Top