fuel problems

[tallyvegas]

hello
i have 1993 2.5 efi 265 hp on a vegas xt , i took it out yesterday, went about 10 miles up river went to leave 2 hrs later , motor would rev up then try to shut down motor would only idle , i idled it for about a hour then i took a pair of pliers and pinchedof the return line . after that it ran perfect all the way to the landing. what is going on. HELP

[rickriddle]

sounds like bad regulator is it efi ?

[tallyvegas]

yes it is

[vector mike]

The regulator has my vote too. If you had to restrict the flow, that is what the regulator does is "regulate" the flow.

[pyro]

Unless it's another EFI problem of some kind, perhaps a faulty vaccuum TPI causing it to only be able to idle, but stall when you give it throttle. A bad TPI or MAP sensor could do that. Pinching the return line would raise the fuel pressure to the fuel pump's maximum capability, probably around 60 psi. This would richen the overall mixture any maybe allow it to run. Just a crazy idea. A bad regulator is more likely...

[rickriddle]

get a fuel pressure gauge and check your pressure per mercury manuel. this will tell you for sure if its your regulator.