Continual Vapor Lock...

[89SE-ICoupe]

Could anyone share some insight with me as to why I seem to get vapor lock when I make frequent around town trips? All that I do is open the gas cap to relieve the pressure, then it starts up immediately. Any insight is welcome.
Thanks,
89SE-ICoupe

[DBMaster]

Vapor lock should be impossible with a fuel injected car. The fuel pump is in the tank so it always sucks up relatively cool, liquid fuel. The entire fuel system from there forward is maintained under constant pressure and is sealed.

Vapor lock used to a problem with old carbed cars that had a mechanical fuel pump attached to the engine. Since the fuel system was open at the carb you could end up with air bubbles in the fuel line between the pump and the carb or between that tank and the pump. There was also another problem called "hot soak" where the fuel would evaporate out of the bowl in the carb and result in a lot of cranking the engine to fill it back up to start the car. I have personal experience with this on my old car.

You are most likely having some other problem on your FI Accord.

[89SE-ICoupe]

Thanks for the in put, I am going to consult my Haynes manual for more ideas.

[fistface]

89SE-ICoupe

Did you come up with anything? I've got the same problem.

[89SE-ICoupe]

Fistface, I haven't found the problem yet. I have not had the time to check it out. I will let you when, or if, I find out what is causing the problem.

[POS carb]

check the charcoal canisters (the fuel vapor scavanging system) follow the haynes manual or shop manual's instructions for testing them, especially pay attention to the vacuum line testing. last resort, drive without a gas cap :p

[HostileJava]

You could still have vapor lock if your fuel was getting heated before it got to the injectors even with fuel injection could you. Say if for some reason the fuel line was rerouted.

[oldriceracer]

what exactly is vapor lock?

[HostileJava]

Vaporlock is when the fuel turns to vapor before it hits your fuel rail/fuel injectors.

[oldriceracer]

oh ok thanx

[oldriceracer]

is that the only place i can get vapor lock? like could i get it in the AC system with the freeon? and if it happens, how do i fix it???

[socal3rdgen]

i always get pressure when i unscrew the gas cap. I think its because i always ruin my car below E. when ever i have very little gas i always hear a psssttt. yes my car is fuel injected.

[88LXI]

did you try replacing the fuel cap? maybe its not venting

[DanG86LX]

So ppl here don't complain of Vapor Lock as DBMaster explained us but rather about excessive vapor pressure in the gas tank! Well, the culprit seems to be the so called.. two way valve. Both FI and Carb have it. I used to have so much pressure in my tank that i was scared the tank might explode. Certainly the cup itself is like a safety pressure relief valve.
But where is this two way valve? When servicing the fuel pump from the trunk, is mounted there on one of the studs around 5 o'clock and is quit difficult to even see it. But from inside the car (removing the rear seats) is quite visible around 11 o'clock. Removing it is a bitch though. One might have to lower the tank a little. I actually manage to bypass it by rerouting one of the red rubber hoses going to it. Pulled one from a lude at boneyard and put it in the engine bay by the charcoal canister.
What does the two way valve do and how can be test it: well there is a vapor line from the tank going to liquid-vapor separator (the strange goose neck inside the fender by the filler pipe) then to the 2 way valve and from there to the charcoal canister in the engine bay. One may test this valve by unplugging the little red hose from canister going through the firewall and applying pressure/vacuum to it. The manual says it should hold pressure of 0.2 - 0.6 inHg (charcoal to tank) and 1 - 2.2 inHg vacuum.

Sorry for long post but might help u ppl.

[AccordEpicenter]

Hey guys the gas cap isnt suppost to vent in these cars!