Dirtman
Former Middleweight Moss Fighting Champion
- Joined
- May 28, 2018
- Messages
- 19,304
- Reaction score
- 13,327
- Points
- 113
- Location
- 41N 75W
- Vehicle Year
- 2009
- Engine Type
- 2.3 (4 Cylinder)
- Transmission
- Automatic
- 2WD / 4WD
- 2WD
- Total Lift
- It's up there.
- Total Drop
- It's down there.
- Tire Size
- Round.
- My credo
- I poop in the furnace.
For literally 3 years I've been chasing strange high fuel trims. Not high enough to set a code of effect the performance much but still enough to make me constantly suspect a vacuum leak.
I checked every way I could and never found a leak so I gave up and just accepted the fuel trims on my truck are just high for no reason. (Ltft around +12%)
Today I happened across a video about 2009+ Ford EVAP purge valve failures. Test was simple, unplug the valve and it should be 100% closed, then pull the line off going to the fuel tank and stick your finger on the nipple. If you feel suction it is leaking and therefore causing a vacuum leak...
This leak will not show up with a starting fluid test (spraying starting fluid around the engine) or even a smoke test because the leak is coming from all the way back at the fuel tank.
Sure enough mine failed the test, not a major rushing leak but definitely not sealed and enough to explain at least a slight raise in fuel trim. The computer also can't detect this leak since the computer only detects leaks when the system is purging.
So just an FYI... Applies to ALL Fords 2009+ according to the video.
I checked every way I could and never found a leak so I gave up and just accepted the fuel trims on my truck are just high for no reason. (Ltft around +12%)
Today I happened across a video about 2009+ Ford EVAP purge valve failures. Test was simple, unplug the valve and it should be 100% closed, then pull the line off going to the fuel tank and stick your finger on the nipple. If you feel suction it is leaking and therefore causing a vacuum leak...
This leak will not show up with a starting fluid test (spraying starting fluid around the engine) or even a smoke test because the leak is coming from all the way back at the fuel tank.
Sure enough mine failed the test, not a major rushing leak but definitely not sealed and enough to explain at least a slight raise in fuel trim. The computer also can't detect this leak since the computer only detects leaks when the system is purging.
So just an FYI... Applies to ALL Fords 2009+ according to the video.