BTrip

1986 Mustang(Project Car) will not stat on it own. (A little staring fluid and start rest of the day) But after trying to start (Cold Motor) I got engine pings and clicks. Thinking Maybe electrical, I disconnected battery and the pings & clicks continue. This start after removing the thermostat. I have a video of this on youtube

dawson1112

Check your fuel pressure, I bet you have a leaking check valve in the fuel pump, this allows the fuel to run out of the rail and let air in . This will result in extended cranking or no start when its allowed to sit over night.

Hook up a fuel pressure tester to the Schrader valve on the rail first thing before you start it for the day. Have some one prime the pump using the key, I would bet your gonna get a lot of air out before you get any fuel . If you purge the air out of the line by priming the pump several times and relieving pressure till you get solid fuel I bet the car would start with out starting fluid.

BTrip

I did this first thing today. I tested the fuel pressure 30 PSI with Vacuum to the fuel regulator and 38 PSI with No Vacuum to the fuel regulator. I am still using starting fluid to start. But now I have to start ever time using starting fluid. Will not start without it.

dawson1112

You need to check the fuel pressure with the car not running to see if it bleeds off while it sets. My point is the check valve in the pump could be letting fuel run back into the tank.

With you gauge hooked up turn the key on and prime the pump , then leave it sit and watch your pressure. If it is dropping off as it sets then fuel is running back into the tank causing air in the rail.

BTrip

Thanks the pressure drop right off as you said. I will be pulling the fuel tank to inspect hoses & Pump

dawson1112

Before you go pulling the tank, get your self a new fuel pressure regulator. A lot of times those get stuck partially open and fuel drains back into the tank that way. It really can only be a couple things. Either the injectors are stuck open ( in that case it would run like poop ) , or the fuel pressure regulator is leaking back , or the pump needs replaced due to faulty check valve .

Also I bet if you prime the pump 4 or 5 times and crank it the thing will start once it pushes all the air out .

BTrip

I replace the fuel pressure regulator on Saturday, it was the first thing I replaced. As for priming the pump it would not start. I will let you know what I find when I pull the tank.

Thanks

petrock

As dawson1112 mentioned, you’ve got a leak in your fuel system. Assuming the gauge was securely attached and the gauge wasn’t leaking, either the fuel pump check valve is bad, one or more injectors are leaking, or a fuel line is leaking somewhere. A quick way to test which one is to take a set of needle nose vise grips and some scrap hose. Slip the scrap hose over the vise grip teeth, have a buddy prime the fuel pump a couple times till you have good pressure. Then clamp the vise grips on the flexible fuel line in the engine bay. If the pressure stops dropping then the leak is between the grips and the tank. If the pressure continues to drop, then the leak is between the grips and the fuel injectors.

Good luck...

BTrip

Hi, after the car been running and I shut it down you can hear what sounds like fuel being siphon from the fuel rails I hear a lot of clicking sound like the injectors are acting like vents for the fuel to drain back tank?. I will test with the vise grips and post today.

Thanks

BTrip

I replace the fuel pump. The pressure is stable but it will not start on it's own. Having to use starting fluid to can it to run, once it starts it running great.