Heat soak / hot misfire

[malcolmzilla]

Hey Folks,

92 Exploder, 95K, stock ignition / fuel system. Platinum +4 plugs. Original plug wires.

Occassionally, when restarting the truck when still hot, the truck misses, barely idles without bumping the throttle, any ideas what is could be? Goes away after getting underway, usually after 100 yards or so. This usually occurs on hot summer days, not a problem in winter. It did this before the plugs were changed last year,too.

Perhaps the plug wires get heat soaked and dont conduct? Or could it be a fueling issue (can EFI vapor lock?)

Thanks.

 

[MrShorty]

Could be a fueling issue. I would put a fuel pressure gauge on it, when it acts up (is it predictable enough?) and see what the fuel pressure looks like. Could also check the vacuum line to the FPR for gas (gas=bad FPR)

 

[Rhett]

Are you getting any check engine codes? The FPR was a very good suggestion by Mr. Shorty.

 

[malcolmzilla]

No, it's not very predictable at all. Just seems hot days / hot underhood. Will check the FPR, thanks.