$480 later and still no clue
09-15-2017, 05:08 PM
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$480 later and still no clue
Greetings to everyone!
I've got a 1999 F150 XLT 5.4L 4X4 Off Road model with 140K miles.
It's been a great truck, however, when the outside air temp is above about 80 degrees, and the truck is warmed up good, it starts to miss, acts like its vapor locking despite being injected. It gets progressively worse to the point I have to stop and let the truck cool down for an hour or so. At that point when stopping it'll die, my luck dictates mostly in the middle of an intersections... The truck runs great at night with the lower temperatures. I've had the truck to two different dealers both of whom were unable to duplicate the problem (cooler days). $480 spent so far and not a clue.
This truck had the same symptoms a couple years ago, and it was found that the plastic evap return valve on the upper aft end of the gas tank was broken. After it was replaced, the truck ran normal,mum until recently.
The truck does not throw or store any codes.
This is what's been done so far:
1. Replaced the fuel cap
2. Replaced the fuel pump
3. Replaced all the coils
4. Had the evap system pressure and smoke checked.
5. Fuel pressure checks good
6. One dealer says they looked for vacuum leaks but found none.
I know there's a solution to every problem. Having said that this chump has been stumped.
I'm thinking about sending the ECU/PCM in to be tested. There's a fella on eBay who will test and fix, plug 'n play, abrogating a trip to the dealer for vehicle specific programming.
I'm pulling straws from the air. R&R components at random I guess.
Has anyone experienced this type of problem?
Better yet, can anyone solve this riddle?
Thanks so much for reading.
I've got a 1999 F150 XLT 5.4L 4X4 Off Road model with 140K miles.
It's been a great truck, however, when the outside air temp is above about 80 degrees, and the truck is warmed up good, it starts to miss, acts like its vapor locking despite being injected. It gets progressively worse to the point I have to stop and let the truck cool down for an hour or so. At that point when stopping it'll die, my luck dictates mostly in the middle of an intersections... The truck runs great at night with the lower temperatures. I've had the truck to two different dealers both of whom were unable to duplicate the problem (cooler days). $480 spent so far and not a clue.
This truck had the same symptoms a couple years ago, and it was found that the plastic evap return valve on the upper aft end of the gas tank was broken. After it was replaced, the truck ran normal,mum until recently.
The truck does not throw or store any codes.
This is what's been done so far:
1. Replaced the fuel cap
2. Replaced the fuel pump
3. Replaced all the coils
4. Had the evap system pressure and smoke checked.
5. Fuel pressure checks good
6. One dealer says they looked for vacuum leaks but found none.
I know there's a solution to every problem. Having said that this chump has been stumped.
I'm thinking about sending the ECU/PCM in to be tested. There's a fella on eBay who will test and fix, plug 'n play, abrogating a trip to the dealer for vehicle specific programming.
I'm pulling straws from the air. R&R components at random I guess.
Has anyone experienced this type of problem?
Better yet, can anyone solve this riddle?
Thanks so much for reading.
