Help! I have a 1998 Accord LX with the 2.3 VTEC. The check engine light is driving me crazy. It came on first about three months ago. I had it coded and it turned out to be P1456 which is "fuel pressure/temperature gauge malfuntion". I was told that meant my fuel cap wasn't tight. The light was reset with no more probs for about a month. Then the light came on again, with the same code. I bought a new fuel cap from Honda and went for about two weeks, when, you guessed it, the same code came up again. I reset if again and now the light is back on in a day. Also, I'm getting about 320 miles to the tank, instead of the 380 or so I used to.

Anybody know what's up? If so PLEASE HELP!

 

I'm pretty sure the 8/80 emission warranty extension applies to this problem.
There are valves that control the evap. system , they sometimes stick or don't open. There is a black box under the car, driver side rear seat area, that has those valves. It's a complicated procedure to check the system....I'll post back with a link..might take a few mins..
http://members.troublecodes.ne...7.zip


Modified by hondadude at 3:23 AM 6/13/2004

 

thanks for the attachment, that gives me a direction to go. I'm going to get a day off next weekend to try it all out. Can you tell me where you got that information? Is there some place online where you can plug in a code and find out what to check, or do you have to be a dealer to get that info so that you can charge hundreds of dollars?

 

I didn't bother to look at that .zip file, but P1456 is "EVAP system leak - fuel tank system"

I don't know where you got pressure/temperature gauge out of that, but if AutoZone read the code maybe they looked it up in the wrong list?? Codes with a number less than P1000 are supposed to be the same for ALL car makes, but above that each carmaker can write their own meaning to the code.

That's the code you'd get if you forgot to tighten your gas cap. Basically it means your gas tank isn't airtight. There's TONS of ways for it to leak, but a loose gas cap is sorta common & easy to fix. Maybe you've got a leak in the tank itself?

The best way to find this stuff is get a shop manual from http://www.helminc.com. That has about 8 pages of detailed stuff to check out for that code. It's a pricey book but it's worth it if you want to work on your car.

It bugs me when someone reads a code & says 'it's your xxxx sensor'. All the code means is which SYSTEM is messed up. It could be a dozen different things, including a split vacuum hose. You don't know which until you do the detailed checks.

 

1456 & 1457 both pertain to the exact same system. Unlike some of the people that post on this website, I do not and will not provide false or mis-leading information. Jim, I have just left the Honda business after 20 years of being a professional technician; and I do not have a hidden email address. Perhaps you should contact the webmaster of this site if you have concerns about my posting.

 

I don't have any concerns about your posting, but the firewall at work sometimes blocks .zip files. When I started posting here with my email available, I began getting an incredible amount of spam & virus-laden stuff. I wish this site had a way to forward email without disclosing email addresses in clear text. That's just asking for someone outside of H-T to do some data-mining...

According to my Helm book, P1456 & P1457 are both about the EVAP system. But somehow it's segregated into 2 parts. By closing ond/or opening different valves, the ECU can apparantly tell the differnce between a leak in the tank vs. a leak in the canister. For each of those codes, there's a different set of hoses & valves to check.

ps...
OK, first I was too lazy to virus-scan that file, but I've done that. It looks like the same kind of checks that are in my Helm shop manual - checking various hoses with a MityVac to see if they hold vacuum, & exercising the solenoid valves. But the EVAP canister looks like a different shape vs. mine. But, that's the kind of checks that he has to do.



Modified by JimBlake at 8:00 AM 6/16/2004

 

Thanks for the info. I looked up the manual on Helminc.com, but the cost for the manual is really high for this one problem, I believe, $70! Is that the only way? Is it the easiest, or most reliable or what? Usually I try to do work myself, but this time I may end up at the shop.

Isn't there a line that runs from the fuel tank to the engine somewhere that is supposed to carry vapors from the tank to be burned up in the motor? If that leaks, wouldn't it show up as the same thing as the fuel cap leaking? Am I on the right track?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sergantfalcon &raquo;</TD></TR><TR><TD CLASS="quote">Isn't there a line that runs from the fuel tank to the engine somewhere that is supposed to carry vapors from the tank to be burned up in the motor? If that leaks, wouldn't it show up as the same thing as the fuel cap leaking? Am I on the right track?</TD></TR></TABLE>Sorta, but not quite. From what I remember, that isn't just 'a line', but a collection of valves & a charcoal canister under the rear seat. The line that goes up to the engine would trigger P1457, because I had that code on our '98 Accord. It involved checking that one EVAP line that goes up to the engine.

The Helm book is really detailed about how to check out this stuff. It looks just like the file that hondadude linked, but that one seems to be for '97. Everybody says Chilton & Haynes books are a lot less detailed. I don't have a good place to scan & host a copy of my book, but I know someone who tracked down a copy at a public library...

Besides, if hondadude is correct about the 8/80k emmissions warranty extension, you'd be better off calling a dealer to ask about that. Worst that could happen is they tell you 'no' over the phone...