1997 7.3 Power Stroke Diesel
The problem that I am having is that the truck shuts off while driving. It has always been between 35 to 50 mph. It has happened while on the gas or while coasting. The dash looks like I just shut the key off except after four or five seconds the check engine light comes on as well as the battery charging symbol.
It will do it once or two or three times in a ten or fifteen period of time then run fine for three or four weeks.
A couple of times it started right up as soon as the truck stopped, but typically it takes about ten or fifteen minutes before it will start back up.
It does it on either fuel tank. I have changed the fuel filter, cleaned out the filter housing and the front fuel tank. None of which helped.
Fuel pressure tested normal: 20 plus while cranking, 50 under no or slight load, no lower than ~28 when under extreme load (towing floored up hill).
I have changed the camshaft position sensor which didnít help either. It also shows rpm on the tach when it is turning over but not starting.
The codes it shows (I read these after the second and third episode (disconnected bat. to clear between episodes).) were:
P0344 (only came up the first time) Continuous camshaft position sensor A circuit intermittent (bank 1 or single sensor) Update: P0344 came up once by itself and the truck didnít stall or even sputter.
P0340 (came up both times) continuous camshaft position sensor A circuit (bank 1 or single sensor)
(came up both times) continuous injector control pressure above/below desired
Thatís about it. Any help would be greatly appreciated.
God bless you all, Ed
Also, the vref contact from pin 90 on the PCM
to: the MAP
, Accel. Pos. sensor, EBP
sensor, and the CMP sensor ohmed out at ~350 ohms where it should have been greater than 1000 ohms. I disconnected each component and re-measured with each disconnection with very little change in the measurement (~ 350 ohms). It wasnít until I disconnected the final thing which was the PCM
. It then showed as open. About an hour later I measured pin 90 on the PCM
with the harness off which then measured open. Then when I re-connected the PCM
it measured well over the 1000 ohm normal reading. This continued with each component that I reconnected.
The vref. From pin 90 does measure the normal 5volts during the key on test though.
This seems like it may be related to the problem since the errors are for both the CMP and ICP
system which are both fed by this same vref.
I also wiggled, twisted all the wiring harnesses that I thought could be involved with the truck running but it gave no codes and didnít stall or spudder.
Any help would be greatly appreciated.
Take care and God Bless you all, Ed