5.0 wiring problems

[jtsmustang]

iv done a 5.0 swap on my 88 ranger have everything done but it wont stay running it will star and i can keep it running by hitting the gas but then it dies the second i let off. i have the fuel pump wired through a switch not through the efi harness i don't know if thats a problem or not if anybody knows what could be wrong please let me know i need to get this thing running asap.

 

[doorgunner]

get one of those little fuel pressure gages that goes up to around 60p.s.i. and install it on the fuel rail using the instructions...then see what kind of pressure the pump is putting out at idle & at 1500 & 2000 & 2500 & 3000 rpm's. It won't cost that much & you'll be sure you've got the right pressure with the set-up you have. Let us know what you find out...........anybody else??????

 

[jtsmustang]

i have good fuel pressure its around 45 psi all the time

 

[RedRanger1991]

Look for a vacuum leak. Ive run into that more than once.

 

[fordmandan87]

sounds like your iac (idle air control) valve it is next to the throttle body either you have no power to it or it is bad

 

[jtsmustang]

i hooked a vacuum gauge up im have good vacuum and the iac motor should be workin i tested it and made sure it worked by taking it off and watching it while a friend was hitting the gas

 

[okietheranger]

Maybe u don't have the mass air flow sensor hooked up or u have a leak?

 

[jtsmustang]

i think i might have figured it out i have to somehow link the 5.0 engine harness with the ranger under dash harness but im not sure how it a 89 mustang harness and 88 ranger harness

 

[okietheranger]

my mustang engine is an 89 and my truck is an 85 only tapped into like 3 wires and it starts and runs fine

 

[jtsmustang]

do u know wat wires u tapped

 

[okietheranger]

All I can remember right now is a thick red wire with a green stripe on 5.0 harness to ranger dash harness comming out of driver side fire wall also a think red wire with a green stripe connect together and make sure a black wire with a green stripe on 5.0 harness is grounded well and there was ones more wire can't really remember the color I think maybe dark blue that has a fuseable link piece of wire on it and it oragnally went to the starter solionid on the mustang firewall needs to be hot as well and that got my truck to fire and run well, as for the fuel pump I hard wired it in but I'm gonna change that later to the correct way hope it helps

 

[jtsmustang]

thanks i must have nother problem then because i have all those hooked up