The Check Engine Light blues


macrumors 6502a
Original poster
Jun 21, 2005
Maybe some of you car-savvy forum members can me figure this out. I recently had the oil changed in my 2003 Hyundai Accent, and the next day my amber Check Engine light came on and stayed on. I had AutoZone scan the computer and they came up with a P1401 code, which indicates some sort of fuel system pressure problem. They said that it's frequently caused by a failing O-ring on an old gas cap. So I replaced the gas cap with a new one, disconnected/reconnected the battery to clear out the codes, and everything was fine for about 3 days -- and then the CEL came on again.

I assume this means I'll end up buying a new purge solenoid, hose or hose clamp, fuel pressure sensor or who knows what else. But what I can't understand is -- why would my gas-cap fix seem to solve the problem for 3 days if the problem lies elsewhere?

I'll have to get this fixed by end of November or I'll most likely fail my state inspection. Drat.


macrumors 68030
Jan 2, 2009
how much did you drive it for those 3 days. usually it takes a few miles im not sure exactly how many but it takes a few miles for the computer to register the problem.


macrumors G3
Jul 24, 2009
As above the fuel cap played no part in solving the issue and when it comes to fuel pressure unless the breather was blocked in the cap it was an unwarranted purchase.

If I were you I would get the motor on ramps and check the fuel line and return for damage etc.