Results 1 to 5 of 5

Thread: Fuel Tank Pressure 87 Accord LX 20A1

  1. #1
    DX User
    Join Date
    Feb 2005
    87 Accord LX (Original Owner)
    Southern USA

    Fuel Tank Pressure 87 Accord LX 20A1

    My fuel tank builds up a lot of pressure (I've read most of the "swoosh" posts). I've tried disconnecting the vapor line from the tank (firewall) to the charcoal cansiter and the tank remains pressurized until I open the gas filler cap. Is that correct? I'm wondering if the two-way valve on the tank is not functioning properly, I've read the test proceedure in the manual for the two-way valve which doesn't make sense yet, it would be helpful to know how it is supposed to work.

    The main problem I am having is a hard re-starting (10-20 min) in warm weather. Once it starts there's a small amount of smoke and the rpms are very low an it runs rough for 45 seconds or so then it runs great (choke operation ok). I removed the line from the secondary fuel filter while there was pressure in the tank and fuel squirted out with considerable pressure until I opened the gas cap and relieved the pressure then fuel siphoned back with considerable vacuum. I'm thinking the pressure from the fuel tank is overcoming the float valve and flooding the intake manifold (?)

    Any thoughts or suggestions would be much appreciated.

  2. #2

    Dr_Snooz's Avatar
    Join Date
    Jun 2007
    1989 Accord LX-i
    Fresno, California

    Re: Fuel Tank Pressure 87 Accord LX 20A1

    I've never heard of that two-way valve going bad. ...on anything. I can't see how tank pressure would ever be able to choke the car without it breaking your carb first. That would be a problem all the time, not just during a warm start.

    Basic questions:

    - When was your last tune-up
    - Are you using good gas
    - How old are your fuel filters

    Not so basic question:

    - What happens if you leave the gas cap off entirely?

    "I like to take hammers, and just break stuff, just break stuff." - Beavis

    1989 Honda Accord LX-i Coupe, 240k miles, MT swap, rear disc swap

    Shop manual downloads available here: CLICK TO VIEW

  3. #3
    3Geez Veteran lostforawhile's Avatar
    Join Date
    Dec 2002
    86 hatchback, 1990 Lincoln Towncar
    nowhere GA

    Re: Fuel Tank Pressure 87 Accord LX 20A1

    these cars had a tank over pressurizing problem from new, not just the accords but the prelude as well. it was swept under the table and kept hush hush by honda. I wish I could remember the links, but there were a lot of complaints. the valve can fail, but your cap is supposed to vent the excess pressure before it damages anything. thats why the spring assembly in the caps.

  4. #4

    Join Date
    Nov 2004
    88 LXi
    Knoxville TN

    Re: Fuel Tank Pressure 87 Accord LX 20A1

    Drill a hole in your gas cap. Not a giant one but a nice small breather hole. Dont tell the EPA or drive in California and you will be fine.

    1988 Lxi owner since August 1995
    336k miles running strong!
    Now running E85.

    Oldblueaccord <<< MY YOUTUBE PAGE!

  5. #5

    2ndGenGuy's Avatar
    Join Date
    Jan 2005
    1981 Accord Hatchback, 1984 Accord Sedan
    Seattle, WA

    Re: Fuel Tank Pressure 87 Accord LX 20A1

    I don't think it's a big deal. Mine has done it for over 8 years. My Miata does it too, but it has a sticker by the door that says "remove slowly to release excess pressure." I think gas tanks just do that. I wouldn't worry about it.

Similar Threads

  1. Replies: 3
    Last Post: 01-19-2007, 06:49 PM
  2. 1993 Accord Fuel Tank Replacement - Help !
    By swampy in forum 3geez Accords
    Replies: 2
    Last Post: 03-19-2006, 02:35 AM
  3. dirt fuel tank keeps clogging fuel filters
    By lamontlamont in forum 3geez Accords
    Replies: 9
    Last Post: 12-12-2005, 10:52 PM
  4. WTB: fuel tank for EFI
    By hootymo in forum Trading Post
    Replies: 0
    Last Post: 02-06-2004, 06:55 PM
  5. Fuel Tank Pic
    By A20A1 in forum Carburetor Tech
    Replies: 3
    Last Post: 10-26-2002, 09:54 AM



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
This website uses cookies
We use cookies to store session information to facilitate remembering your login information, to allow you to save website preferences, to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.
VigLink badge