vacuum lock issue?

MA70-3.0GT · 08-04-2010, 03:45 PM

Vapour lock in an EFI system???

~I severely doubt it as the fuel pump is more than powerful enough to force an airlock through the system and if it were sucking air (different to vapour lock but worth ruling out) you'd A) have problems when running not just starting & B) probably hear the pump going crazy on cranking. More likely a dodgy relay or less likely a fuel pump issue.

Have you ascertained that you have a spark when it's no-go? any codes when it's running? If you do have a spark next time it won't start then get a jumper wire & bridge the FP & B+ terminals in the diag box, the pump should then run permanently with ign. ON, if that is the case and the car then starts we know where to look next...

EDIT- Green's linked to a thread below my post now & at the bottom of that is the TSRM page I was thinking of to test fuel pump/pressure, provided your starter's fine of course...

08-04-2010, 03:45 PM	#2
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	Vapour lock in an EFI system??? ~I severely doubt it as the fuel pump is more than powerful enough to force an airlock through the system and if it were sucking air (different to vapour lock but worth ruling out) you'd A) have problems when running not just starting & B) probably hear the pump going crazy on cranking. More likely a dodgy relay or less likely a fuel pump issue. Have you ascertained that you have a spark when it's no-go? any codes when it's running? If you do have a spark next time it won't start then get a jumper wire & bridge the FP & B+ terminals in the diag box, the pump should then run permanently with ign. ON, if that is the case and the car then starts we know where to look next... EDIT- Green's linked to a thread below my post now & at the bottom of that is the TSRM page I was thinking of to test fuel pump/pressure, provided your starter's fine of course... __________________ '89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit... '89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks... '83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks '95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it I'm not paranoid, they really ARE after me!!! Last edited by MA70-3.0GT; 08-04-2010 at 04:10 PM.