Crank Sensor trigger & Fuel Tank Woes

[spf973]

My 2002 8.1 (37K miles) has been back to the dealer 3X and they still haven't fixed it. The gas gauge started fluctuating wildly so they "replaced front and rear fuel level sensors.) Then the truck ran OKAY (real soft at 3K revs, like low Fuel Pressure,) but absolutely dies at 1/4 tank...I mean it runs on maybe 4 cylinders, burping and popping. Unable to climb any grade. Fill tank and it runs a lot better. Okay, next trip, dealer tells me the "Crank trigger sensor" is defective and that replacing that will solve all my issues...I asked him what the relationship between the fuel tank & crank trigger was....Anyway, engine runs fine now (real soft as it's gotta learn all over again, and I am back on stock chip for now,) until I get just above 1/4 tank....Drove back to dealer, and made tech ride along w/ me to experience what 8.1L feels like running on 2L...Made my point, but they are still clueless. Question: since the fuel pump/level sensor is a 1 piece unit, it's not like the sensors could be placed in the wrong location....so what is going on? I keep asking them to replace the pump to be sure, but they have resisted me. The pump does seem to be whining louder.....Help! I need this to tow my race car-either they fix it or it's F-250Diesel time...JM

 

[spf973]

After 3 visits to the dealer, each for three days, over 3 successive weeks, the dealer finally listened to me and fixed the Fuel Tank. I made a tech drive in the Truck w/ me at 1/4 tank...he couldn't deny the lean out (consistent w/ running on empty.)

Well, dealer claims the spare tire can dimple the fuel tank, causing the float on the fuel level sender to hang up on the side of the tank around 1/4 full....Odd that:
1.) I've never used the spare.
2.) It was fine before they worked on it the first time.
3.) They could have checked this out the first time.

So, I caution you all to inspect the clearance between the tank & spare-carefully. And when cranking the spare back up, exercise extreme caution in "snugging " it.

Good luck, JM

 

[7of7]

Did they get the problem fixed? Or are you still having problems with it? If it was fixed, what did they change?

 

[spf973]

It appears to be fixed. They replaced the entire rear or lower main tank, as well as the front & rear (upper & lower) fuel senders, and I believe, the rear fuel pump. They claim there's actually another pump that pumps gas from the small tank to the larger one....although it sure looks like a gravity feed to me....
JM