2005 Ford Escape 4 cyl
240,000 miles
Every time i fill up the gas tank and then drive for a while, either the next time i start the car or while i’m driving, the engine will begin to misfire, lose power, and eventually stall. It won’t start again, or will start but misfire so much that it stalls again. If I wait 20 or 30 minutes or over night, then it will start up and run fine until i fill the tank again a days or so later.
Given those symptoms, I have to assume that the Check Engine Light is lit up.
Am I correct?
If so, then you need to have the stored trouble codes read in order for anyone to begin to diagnose the problem. If you go to Auto Zone, or Advance Auto, or O’Reilly, or (possibly) Napa, they will read those codes for you w/o charge.
Then, you can come back to this thread and post the exact codes for further help.
The codes will be in a format similar to “P0123”.
I agree.
I’m also going to suggest that if you top off your tank when you fill up you discontinue that practice. You could be saturating the charcoal bed through which the gas tank has to breath in as it pumps gas out.
I’ll also suggest that when it exhibits the symptoms described you remove and reinstall the gas cap. If you hear a loud suction sound and the problem goes away, a saturated charcoal bed is a real good possibility. Not a guarantee, because there are a few lines and valves involved too.
Post the codes as well as the results of the “gas cap test”.
Purge valve and the Carbon Charcoal Canister
Code P2196
The engine light doesn’t always come on.
That code is an indication that there is a likely problem with either the front oxygen sensor or the wiring running to the sensor. However, I am having a hard time connecting that with fueling the car.
I think it was a symptom. As I said it doesn’t always get a light. The previous code was cylinder misfire, also a symptom.
I’m surprised to hear so much mileage.Don’t fill the tank to the top,when the pump clicks off when you’re refueling,pull the nozzle out and hang it up.Filling it too high will drown the evaporative emissions system,but I don’t think this is the problem.
Ford is having trouble w/the ecoboost engines.Gunk builds on the non-combustion side of the intake valves from the EGR system,this causes the misfire.
The fact this only happens when the tank is full seems to me it is related to an fuel tank evap system problem of some sort. The evap system is designed to prevent gasoline fumes from getting into the environment, and stay in the fuel system instead. This is good for you as it increases your mpg, and good for everybody else b/c the air is cleaner to breath.
But if that system fails, it can cause air/fuel mixture problems which result in overly rich or overly lean operation and resultant misfiring. The computer might flag this as an O2 sensor problem, but what it is really saying is – given the amount of gas it thinks it is injecting — it can’t figure out why the O2 sensor readings are so weird. The cause for the weird sensor readings though might be the evap system problem, not a faulty O2 sensor.
As posted above, ask your mechanic to check the operation of the evap system, including the canister and the evap purge valve.
Edit: P.S. There’s a test a mechanic can do called “Fuel Trim” that might provide some clues too.
Turns out it was not misfiring, it was running extremely rich. It was a faulty fuel pressure sensor. I tapped on the sensor and the engine just evened out and ran perfectly. Replacement cost was just over $100.
Thanks for the update!