p1457 is because of a vacuum leak or sealing problem in the evap system on the canister side. it usually sets because of a bad solenoid or leaking solenoid.

the most common failure is the canister vent shut valve. next would be the purge control solenoid. next would be spider webs/eggs in the canister vent shut valve vent hose. finally the bypass valve, then canister. this is all assuming the vacuum lines and wiring are ok.

 

Suit yourself, but I have never experienced a Check Engine Light reset itself without having to either disconnect the battery or pullthe fuse. Why not reset it now and find out for sure without having to wait for it and hope it will go off? If you reset it now, and the light comes back on, you know the gas cap not being on tight enough is not the problem. Then you can troubleshoot the gas cap itself, then the evap system.

 

For '98-'02 Accord...
There's a fusebox in the RIGHT end of the dashboard. Open the door & look near the door hinges.
Reset the ECU by pulling the #13 fuse in that fusebox, for maybe 30 seconds. I think this will reset your clock, but it won't interrupt power to the stereo.

The CEL can reset itself after several driving cycles. *IF YOU FIX THE PROBLEM*
It's not always 3 start cycles, not always 5 or any particular number. There's a whole list of things that have to happen, and sometimes you don't drive far or long enough for that to happen. Google something like"OBD-2 Readyness Codes"...

 

Yeah, I will probably end up clearing the code if it does not go away after a few days. Reason I thought I would wait and see is because I have already cleared the code twice via the #13 fuse, and it came back on both times. I have lots of time so decided to see if the self clearing thing would work. But with my luck, I will probably need to eliminate the possible causes, one by one, and it will be the last thing on the list.[&o]

 

Just out of curiosity, what part of the gas cap usually causes the problem? Is it the cap to neck seal or is it the valve in the cap itself?

 

If you reset it and it comes back, that means the problem isn't fixed. Any different method of resetting won't help. Every time you reset it,the computercomes back & finds the problem is still there. You need to find the problem & fix it.

The gas cap is supposed to be airtight - actually, the entire tank. The gasket in the cap can leak, but that would set P1456, not P1457.

P1457 means something in the EVAP canister area isn't airtight, or one of the solenoid valves isn't working. The Helm repair manual has quite a few pages of detailed checks to narrow down the problem.

 

yeah, p1456 = gas cap was loose or faulty(99% of the time). the other 1% of the time is damage from a body shop, rusted fuel fill pipe, some freak problem.

p1457 = canister side leak. usually thebypass solenoid or canister vent shut solenoid - especially if you live in the salt belt states.

 

HondatechAV6---Any chance that you may have some good diagrams helping me to locate the items that you so kindly outlined in your previous post? I cleared the code, but it came back after two days, so looks like I start the process of elimination. I have a Haynes manual but it is pretty sparse.

 

I just looked at Majestic's website, & the parts drawings are scrambled. Gas tank shows me a picture of the transmission housing... maybe it'll be fixedlater.

The EVAP canister is located under the car, belowthe left-rear seat. Before you have a look under, make sure the car's supported securely (good jackstands).

Look for hard, crusty, & split vacuum hoses anywhere around that canister. That would be an easy fix, so maybe you'll get lucky.

The vent-shut valve is mounted in the outboard end of the EVAP canister, sorta out near the rocker panel. When mine went, the solenoid valve wouldn't work at all. So you could get 12vdc (spare car battery?) & use jumper wires to energize that valve. Mine made no sound at all when I did that.

I think the bypass valve is next to the forward side of the canister?? Same drill if you want to check it.

 

I tested the solenoids today. The tank vent valve clicked when I applied 12vdc, and as well, when power was applied, the large hose held a vacume, which released when power was removed. I think that is the way it should work.

The other valve, two way valve solenoid also clicked when 12vdc was applied. However, I was unsure of exactly what to look for in terms of vacume/no vacume. Thelittle valve at the top, with three wires coming in to the control, I was not sure how to check that one.Is that the two way valve???I have read thru the Haynes manual several times but it is very confusing, to say the least.

From what I saw today, I would probably suspect the two way valve, but I am only guessing. I really appreciate any help I can get, and hopefully I will become educated and repair this thing.