Mechanics

F150

1988 Ford F-150

Electrical problem
1988 Ford F150 V8 Four Wheel Drive Automatic 120000 miles

I have a 1988 ford f-150 with the 302, every morning I go out and the truck will start right up and run great all day, when I shut it off it will not start again unless I pull the fuel pump relay out. After it restarts I have to plug it back in and it will continue running fine until I shut it off again. When I try to restart it I do have spark at the plugs, but I can smell the fuel like it is flooding. Any ideas?
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Shanepaye
March 5, 2009.




http://www.2carpros.com/how_to/how_do_i_check_a_relay.htm
If the fuel pump runs with the key off, replace the relay and check the fuel pressure regulator. Pull the vac line off and if there is any gas in it, change the FPR.
Test pressure and regulator this way.
http://www.2carpros.com/car_repair_video/test_fuel_injection_pressure.htm

Merlin2021
Mar 5, 2009.
First thought is you have injectors bleeding down and flooding the engine. Does your engine oil smell " gassey"?

Tiny
James W.
Mar 5, 2009.
Yeah I can smell gas in the oil, does that mena new injectors or whats the easiest way to fix that?
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Tiny
Shanepaye
Mar 5, 2009.
The smell can also be from just cranking the engine without it starting. Do a fuel pressure test and leakdown test with a fuel pressure test guage, it's the ONLY way to find leaky injectors. You do it by watching the gauge for five minutes with the key off, if it losses 5lbs of pressure over the specified time, an injector is leaking.

Merlin2021
Mar 5, 2009.
Awesome thanks a lot for the help

Tiny
Shanepaye
Mar 5, 2009.
I'm sure its an injector, is there any way to fix or is that a replace part?

Tiny
Shanepaye
Mar 5, 2009.
Is the truck getting missfires on any particular cylinders? Those would be the bad injectors, replacing is the only fix for bad injectors, but I still advise the testing.

Merlin2021
Mar 5, 2009.
It doesn't seem to be misfiring at all, when it starts it runs great, its just the restarting that is the problem. It just cranks over and over unless I shut the fuel pumps off manually by pulling the relay, once it starts again I have to plug the pumps back in before it dies again

Tiny
Shanepaye
Mar 5, 2009.
There is one thing here that puzzels me here. I've seen where 1 or 2 injectors will bleed down and when the engine is restarted a couple of cylinders will be flooded and will limp for a bit before they clear out. But I've never seen where all of a sudden " all" the injectors went bad to the point that the engine won't even fire. You may want to follow merlin2021's suggestion and run a fuel pressure bleed down test with a gauge. Keep us posted.

Tiny
James W.
Mar 5, 2009.
Yeah I will do the test and keep you posted, I guess I forgot to mention this all started after I degreased and washed the engine bay. But I checked all connectors and they are all dry and look good

Tiny
Shanepaye
Mar 5, 2009.

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