Hi ! My truck has a 7.3 diesel ! This winter I have been having problems with cold starts ! I replaced all the glow pluggs and now ot starts a bit better but not as good as it did last winter. Now when it does fire up in cold weather it wants to stall. Have to keek foot on gas pedal some times to keep ot runnin. Could this be caused by faulty wires and gaskets feeding the glow pluggs not giving motor enough heat? If truck is plugged in or it is warm out it starts and runs fine !
There is a glow plug controller that controls the time the glow plugs stay on. Get it checked to see if it is bad. Bad idea to throw any parts at it till you find the failure as these parts are very expensive.
December, 12, 2012 AT 12:45 AM
Already replaced that relay and fuel filter to. Runnin anti gel in fuel to so diesel isnt gelling up
December, 12, 2012 AT 12:47 AM
It is not a relay, it is a controller.
December, 12, 2012 AT 12:59 AM
Ya think we r talkin about same thing ! It opens when key is on and sends 12 volts down to glow pluggs for about a miniute then closes. I replaced it cause it was not staying open as long as it should
December, 12, 2012 AT 1:03 AM
Part OEM Part Price
Glow Plug Control Module
Glow Plug Module Assembly FOTZ12B533A $184.92
Disconnect the batteries.
Remove the plastic terminal cover from the relay.
CAUTION : Do not use a screwdriver or similar tool to pry off the terminal cover. Battery voltage is present at the terminals.
Disconnect the battery terminal connector (12 volt power wire), the glow plug relay connector, and the harness connector.
Remove the mounting screws and remove the relay from the engine.
Install the relay on the engine and tighten the screws.
Reconnect the harness connector, relay connector, and the battery terminal connector.
Reinstall the plastic terminal cover.
Reconnect the batteries.
The second is the relay that I believe you replaced. The first is a small computer.
December, 12, 2012 AT 1:55 AM
Ford p # I replaced is f8z-12b533-ac were is other controler located cant find it on my scematic and how do I test it?
December, 12, 2012 AT 1:57 AM
That is only the solenoid.
You need a scan tool to check it. I have never been able to bench test this unit off vehicle.