Fuel Temp Sensor Test

[62Sunbeam]

Ok so I think I've narrowed my rough starting when hot problem to a faulty fuel temp sensor as I've replaced the coolant sensor and the O2 sensors. I even described the problem to the parts guy at the dealer and he thought the sensor is probably bad.

My question is this: The sensor is a resistance type sensor so can I remove it and check it's resistance over a range of different temps? What should the range of impedence be over what temps?

I'd really like to see if I can double check before I shell out $75-225 for a new sensor.

Any and all suggestions appreciated

Eric
95 Disco

 

[discomike]

Not to confuss the issue, have you looked at the fuel filter and fuel pump???
That is one thing they will do to you. Fuel filter should always be changed every 25to 30K, the fuel pump can be wearing out and not able to get the pressure back up real quick when hot and or the there is a valve in the fuel pump that fails and all the fuel in the rail drains back into the tank when left to sit, especially when it is hot. Then it takes a lot longer to crank the engine before it will start.
I would put my money here, just a thought.
Mike J.

 

[62Sunbeam]

I did replace the fuel filter. I did not check the pump. This is why I would like to test the sensor: just to make sure.

I would think that if it were the pump and or the valve it would also act up when the disco has sat for a longer period of time (over night or a few ours in a hot parkoing lot) but it's more like if I park the truck for five or ten minutes on a warm afternoon after heavy traffic it's the worst. Very exterior temp sensitive.

My point being if the problem was with the pump or the check valve the problem would also happen after a long commute in hot weather and then get parked over night Gas would run out because the truck is hot and It would be hard to start in the mornining as there is no way for the gas to run back into the FI system. As it is it always starts right up and runs great when warmed up on a cool morning.

Basically I have a hunch it's the sensor and I'd like to rule it out before I move on to other things.

Thanks

Eric
95 Disco

 

[discomike]

Eric,
When you are driving on an old fuel pump on a hot day with worn out brushes, it take way to manmy amps to turn the pump over hence a no start. Let it cool off and the pump will turn over easily again.
Mike J.

 

[Coronan]

This thread didnt answer the OP's question. Which is my question.

How can we test the Fuel Temp Sensor?

Ive couldnt find it in the pdf manual. Only how to R&R?


THANKS.

 

[Disco Mike]

You would be better off testing your fuel pressure, especially when hot as your old D1 most likely has a warn pump and more so a failing fuel rail caused from the original coating used inside the rail which with time, heat and all the bad gas will start to brake down and plug the injectors.

 

[davidrosenbloom]

Ok so I think I've narrowed my rough starting when hot problem to a faulty fuel temp sensor as I've replaced the coolant sensor and the O2 sensors. I even described the problem to the parts guy at the dealer and he thought the sensor is probably bad.

My question is this: The sensor is a resistance type sensor so can I remove it and check it's resistance over a range of different temps? What should the range of impedence be over what temps?

I'd really like to see if I can double check before I shell out $75-225 for a new sensor.

Any and all suggestions appreciated

Eric
95 Disco

Any luck with r and r wo removal of fuel rail?

 

[davidrosenbloom]

09 rr 4.4 looking to r and r fuel sensor wo removing fuel rail… tips?