I been having problems with my car starting sometimes when it is extremly hot outside. I just did a tune up (spark plugs, wires, etc) and the starter, distributor, battery, alternator, etc. are fine. A mechanic told me that I have vapor lock most likely. Anyone heard of "vapor lock" and does anyone know how to fix the problem?

 

how old is the car? never heard of that before "vapor lock"

 

It's not that old.. it's only a 92 Honda civic hatch with a JDM B16 (SI-RII).

 

My car not starting seems to be fuel related b/c sometimes when my car doesn't start I open the gas tank cover, unscrew the cap (which releases gas vapors), and then I start the car and it starts.

 

Vapor lock is caused by a fuel getting to hot/boiling.. I have had this problem with my carbureted chevys, but never on a Honda.

 

it might be a bad main relay they cause the problem that when its hot outside it wont start and after it cools down in the car a little it will start ... just a thought i would throw out there ... sence i never heard of a honda vaporlocking

 

I bet you he has his gas tank vent capped off in the engine bay and got rid of the evaporation canister.

 

I bet you that if you notice that your fuel pump isn't priming it's your PGM-FI main relay.

Here jOo go:
https://honda-tech.com/zerothre...36514

<FONT COLOR="red"> Your welcome</FONT>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVTEC 91 Civic &raquo;</TD></TR><TR><TD CLASS="quote">Vapor lock is caused by a fuel getting to hot/boiling.. I have had this problem with my carbureted chevys, but never on a Honda.</TD></TR></TABLE>Older carburated cars have a fuel pump that sucks fuel out of the tank. So the fuel in the line from the tank is at a partial vacuum, it vaporizes more easy, then it can't be pumped. Vapor lock mostly went away when they put electric pumps inside the tank.

Flakey main relay would be a likely guess.

 

Cool... I'll check the main relay and tell ya'll what happens. Thanks for your help.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeffb16 &raquo;</TD></TR><TR><TD CLASS="quote">Cool... I'll check the main relay and tell ya'll what happens. Thanks for your help.
</TD></TR></TABLE>

no problem man, let us know

 

Yup; vapor lock happened in older carb'd cars w/ low-pressure fuel systems. That is why in hotrods they would run an "icebox", which was a coffee can full of dry ice where they ran the fuel lines into it to cool off.

The problem was eliminated w/ the incorporation of high-pressure fuel systems and fuel injection.