Got this code a while back (several hundred miles) but have had no runability problems. I know it's the evap canister but my mechanic tells me it could be a myriad of things and he might spend hours on it and still not be able to resolve it. I plan on driving this truck til it's worn out. I've put 125,000 miles on it in 10 years almost all highway. I should be putting much fewer miles on now, only using it when I NEED a truck which should be less and less, mostly for hauling toys. I hate to drive this thing another 10+ years with the engine fault light on but my mechanic says that if something serious goes wrong it will start to flash. A couple days ago the "check fuel cap" warning came on, but goes off if I hit,the odometer button. I got a new gas cap at Reilly's but it seems like a real POS compared to OEM, very light, and the check fuel cap warning still comes on. Anyone have advice? I hate to just give the dealer my CC.

 

First would be for you to tell us what year and model of truck along with what engine. The check engine light will not flash it just turns on to tell you there is an issue. Any problems fueling up is it really slow or cut off early hard to get all the way full any thing like that? You can get a new ford gas cap for like 15-20 bucks lots of us here get parts form here AutoNation Ford White Bear Lake | Parts & Accessories they have good prices on OEM parts.

 

No I hadn't noticed any difficulty filling it up. I don't have my owners manual in front of me but I thought I had read that the "engine" light will come on for a problem, and it will flash for "serious" problems.

 

Check your fill up neck - might be rusted thru or rubber connector cracked. On my old f250 it was rusted so bad that it started to leak.

 

You might want to try a different "mechanic".

Your code indicates a problem with the fuel cap or the vent control valve. Actually, it could be caused by any leak in the EVAP system or a problem in the electrical control of the vent control valve. EVAP systems are not that hard to troubleshoot, IF you understand how they work. If you like to guess, the first step might be, get a new OEM fuel cap.

The only real problem that it is likely to cause long term is not being able to pass an emissions test.

Remember that the CEL is NOT an engine diagnostic monitor. It IS an emissions monitor. The CEL ONLY comes on when a fault causes the emissions to be outside the programmed limits for your vehicle. The CEL will flash if the fault is bad enough to cause damage to your catalytic converters (i.e. extremely rich fuel, etc.).

Find someone who understands EVAP systems and it should not be hard to locate and fix the problem. "TEST, Don't GUESS!!"

 

Got a new OEM on its way from the source suggested in an earlier post. We'll see what happens from there. Thanks!!