Annoying start up issue 1995 Mustang GT 5.0

[lucid]

1995 Mustang GT 5.0

Hi gentlemen,
I have this 95 GT which appears to be bone stock. Previous owner traded it in for a newer mustang
about 10 years ago and I bought it from a friend of the dealership that sold off the trade ins. It's always
had this issue where it would crank and crank but not fire up immediately. I usually have to turn the key off and on
about 3 times to prime it up enough to where it will fire. When it does fire up, it's not butter smooth like my TPI engine, it chuggles and sputters and runs a bit rough. After it's on it revs up and smooths out. It does seem to have good power and pulls pretty strong. Sometimes when you a cruising about 40mph it will start to have this small miss and a slight shake, and the check engine light will randomly come on and turn off. Any suggestions would be appreciated. I ordered a Motorcraft ignition coil from Amazon and it will be here shortly.

Recently got it back from the mechanic: new wires and spark plugs, cap and rotor.

 

[lutter94]

Have you ran fuel pressure tests? Auto parts store should have the tools. If repriming it helps, that seems to point towards fuel issues....

 

[ReplicaR]

I've had the same issue, it was fuel pressure. To be more exact, my fuel pump was not building enough, and on top of that my fuel pressure regulator leaked fuel into the intake manifold. Changing both fixed all start up issues.

 

[RichV]

I was going to say fuel pressure as well.

FPR, filter, or pump would be my guess.

 

[Johnnym1]

I would monitor fuel pressure and for sure check the codes

 

[lucid]

Thanks for all the replies. I was almost sure it was a dizzy or coil issue but now I am starting to think it's something with the fuel because it acts like a carb'ed car that has been sitting for awhile. I'm going to look for a place nearby that can change out the fuel filter and then borrow a fuel pressure tester.

 

[lutter94]

filter swap is easy, pick one of these up, back up onto a set of ramps. Its right in front of the tank

 

[lucid]

I bought a Motorcraft fuel fitler from Advance and asked the counter guy if he knew any places he trusted to pop one in. He called his mobile mechanic that hangs out there and the dude put it in for $20. He turned the old one over and brownish liquid came out, like a muddy water. I swapped out the ignition coil with a Motorcraft unit and ran the tank almost empty and added a bottle of Techron to a full tank of gas. It's definitely better now, I don't have to crank quite as long or prime it as much. I found a high pressure line going to the fuel rail with this dink plastic clamp so I put a real fuel pressure clamp on it because it was barely on.

At cruise around 40mph there is a definite miss and it sets a code. The next thing is to check the pressure and check the codes. I've been staying with my mom in the hospital for 8 hours a day every day for 13 days straight so I try to sneak in some time to mess with the car.

 

[lucid]

Hey guys, it's been awhile but I have had 2 surgeries in the past year, so I've been busy. Things i've done to the car:
-New Motorcraft fuel filter
-New Motorcraft fuel pressure regulator
-New Motorcraft ignition coil
-New Spectra distributor

The car turns over fine. When I turn the key to run, usually I can hear the fuel pump prime but it's really really faint, like I can't hear it over the chime from the car speakers. After I work the key off and on a few times, I will hear the true loud full prime and it will attempt to fire. Sometimes just cranking it, it will eventually give you a good loud prime and start.

Should I be looking in the CCRM for a sticking relay or perhaps be worried that my fuel pump is getting really old? The A/C works fine and the radiator fans seem to be operating normally.

I pulled the codes with an old school Scantool with cartridges and got a couple codes. One of them was a lean 02 sensor code, which I don't think would affect starting because that should be open loop.

Any suggestions?

 

[ponyboy88]

A replacement style fuel pump is not that much and good piece of mind in a 20 year old car. You can buy a higher flow rate if you think you will be making further upgrades in the future that will require more fuel. Since it's a return system the extra flow will just get returned so it will work on a stock car in the meantime.

 

[rz5.0]

Lean code means your not getting enough fuel or vac leak.. I would get a 255lph fuel pump.. There like a 100. Also check for vac leaks

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