6.4 trouble

[blacksnapon]

Had one come in complaining of no power. Checked and found a code for fuel temp. His degas bottle cap was loose and the anti freeze level was way low. The low anti freeze was causing an overheat condition making the fuel coolant dtc come on which will cause a "de-fuel" in an attempt to reduce the heat. There was no obvious other cause of the overheat other than the loose cap. Filled him back up, tightened the cap, cleared the dtc, so far, no comeback.

 

[6L PWR]

Ya gotta love today's modern electronic controls. ROFL Maybe he should just pull those sensors off.ROFL

 

[mrfixit]

In big trucks for YEARS we had what was called the KEYSOR engine sensor system. a rudimentary predecessor to today's engine computers. More than once I had guys complaining that their engine kept shutting down. I'd ask if they'd recently run low on coolant, and 99% of the time, they had. They'd refilled it, OK, but once the water level would drop below the sensor, the sensor element oxydized and was basically worthless from then on.

 

[Brian_B]

That is interesting. I would have been in trouble in the old truck a while back if that happened. LOL

 

[Rusty Shackleford]

In big trucks for YEARS we had what was called the KEYSOR engine sensor system. a rudimentary predecessor to today's engine computers. More than once I had guys complaining that their engine kept shutting down. I'd ask if they'd recently run low on coolant, and 99% of the time, they had. They'd refilled it, OK, but once the water level would drop below the sensor, the sensor element oxydized and was basically worthless from then on.

I had an F-650 with a C7 Caterpiller last week. The "Stop Engine" light would come on because the coolant was less than an inch low.

 

[mrfixit]

I had an F-650 with a C7 Caterpiller last week. The "Stop Engine" light would come on because the coolant was less than an inch low.

That's the kind of thing I was talking about. Those sensors get to where they will even go into shutdown mode when the coolant level is fine. another problem they had was when drivers would "temporarily" top it off with water, making the coolant WEAK... also corrodes the sensor.

 

[sdtheclub]

The fuel system has it's own cooling system so you will be having a recheck. Everyone I have had so far needed the cooler bleeding. You have to remove the cooler for the fuel system which is the one on the LF and turn it upside down and wait for all the air to come out at the little coolant bottle which is mounted to the fuel cooler.