Possible fuel system problem...looking for some help

[kevinkraiss]

Hey guys, so it seems like everything has been going down the tubes with my Explorer this month. I should probably start from the beginning.

I bought my 2004 Explorer (4.0L FFV) In August 2012. Everything has been relatively good up until about a month ago. I'm being plagued by the common rough idle accompanied by check engine light. I started out by cleaning the MAF, IAC, and throttle body, and that improved it, but didn't completely fix the problem. I had the codes checked and it was reading fuel mixture too lean (not sure of the exact code, sorry). I tolerated it until last week, when my Explorer died while driving home from work. To make a long(er) story short, I ended up killing the battery, and somehow erasing the key microchip memory. I had to pick up a new battery, cut another key, and get a reprogram. My check engine light and everything got reset, but came back on after roughly 300 miles. A few days ago it died around a quarter tank of gas again. This leads me to believe that either the gauge is broken, or maybe it's a fuel pump problem? I dumped more gas in it and it started back up fine, I drove it home with no problems. I have also intermittently had the flashing check engine light (misfire I believe?), and I always have to fill up slowly to avoid the gas pumps shutting off on me every 10 seconds.

So my question for all you experienced troubleshooters out there is this: What causes rough idle, O2 sensors reading lean, fuel gauges reading improperly, intermittent misfires, and incredibly slow fuel fill-ups? Any and all help would be greatly appreciated! Thank you!

 

[chopperb]

1. Check the canister vent solenoid hose for any obstruction and clean or repair as needed. Also if an inspection camera or borescope is available, check in the filler neck for any debris or restriction. Some of these vehicles have a filter screen in the metal part of the filler neck that can get plugged with debris.

2. If the vent hose and filler neck are not restricted, remove the canister vent solenoid from the canister. Verify that it is open and free of any restrictions. If not, replace and retest.

3. If the vent solenoid is OK, check the charcoal canister for any restriction. Repair/replace as needed and retest.

4. If the canister appears free of any restriction, remove the fuel vent hoses as close to the fuel tank as possible. Try filling the fuel tank with the hoses disconnected at the fuel tank to see if it fills as it should, or if the gas pump still wants to click off too easily. If the problem is still present, suspect a problem with the vent valve(s) in the top of the fuel tank or a problem at the fuel inlet to the tank.

 

[kevinkraiss]

Awesome! Thanks a lot. I'll run through it in the next day or so and post the results.