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Discussion Starter #1
1995 Tbird 4.6..93k Miles.

Was starting fine until I got the car back from the shop after replacing both front motor mounts.

If you start it after a short rest it?s fine.

However, the 1st start and then say at lunch time and then again when going home in the evening, it will have a long crank, 5-10 seconds. If you let off the key and try again, it fires right away. If you go somewhere and come back out, it fires right away like normal.

Usually it?s touch the key and it fires off.

No CE lights, drives fine.

Ideas???
 

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Slow leak in the fuel line; fuel pump, FPR, injector.

What you can do first time when it's cold is turn it on but don't start; wait 10 to 30 seconds; turn it off for 30 seconds.

Might take two or three passes.

That reprimes the fuel line and the fuel rails, and gets you back to an "instant start".

RwP
 

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My 5.0 takes about 1.5 seconds when sitting for a while. Go on a drive, get back in car and it'll start right up... But yeah, that long sit, cold start takes longer.. I put a fuel pressure gauge on the rail and it read ~40psi, so I was in the right range, just sometimes it likes to crank a bit..
 

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The fuel pump is allowing the fuel to drain back to the tank. Try turning the key on for two seconds before starting. If it fires right up, that is likely it.

I had the pump replaced on my 95 for that reason. It fixed the problem 95%, meaning it still did it on occasion, but not nearly as long.

Al
 

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interested since i could have the same issue on my 5.0. i won't run the starter for even 5 seconds though. if it doesn't fire right up i release the key and it fires up the next time.


ETA
i have no idea what's going wrong but i never run the starter a long time. it seems like it has to be a fuel supply issue and not electrical. i like the response by T6Rocket earlier about the fuel being allowed to drain back into the tank. that could be a faulty check valve in the fuel pump or system but it's not a problem worth changing out the fuel pump to me. i read here it's expensive and a pain to do.
 

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If the cam sensor had issues, it will turn 4 times or more to fire.
 

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I have asked the same question a few times. My Cougar takes a few seconds to start sometimes. Tbird always instantly fires up, even though it has twice the mileage.

My Cougar had a no start issue a while back. Spraying the crank sensor plug with some contact cleaner got it to start; problem hasen't returned. So I think that could possibly be related to the longer crank time. I bought a new harness to splice in but haven't got around to it yet.

Since you recently had it worked on maybe the harness got bumped and is causing an issue?
 

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Discussion Starter #8
Replaced the FPR.....the issue continues.

If you crank it long enough and it doesn't start and let off. Then turn the key right back to start it, it starts immediately. Then starts fine all day long as long as it doesn't sit too long (start of work to lunch, then lunch to leaving to go home)
 

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Just noticed you're in Vegas too.

You did say it was after replacing the motor mounts that you had this issue, try checking if any wiring around the motor mounts isn't yanked or loose when they were working in there. Also my dad is a partner at a new shop here in Vegas called Auto Xperts on Silverado Ranch. Bring it by, my dad should be there and they'll diagnose it for free.
 

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Discussion Starter #10
Hooked up a fuel pressure gauge today after it’s been sitting for a day or two. Had zero pressure in the rail.

Turn the key on...pressure jumped to 20psi and pump shut off.

Turn the key on again....pressure jumped to 30psi and the pump shut off.

Turn the key on again...pressure was 40psi. This time I started it and fired right away.
 

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Hooked up a fuel pressure gauge today after it’s been sitting for a day or two. Had zero pressure in the rail.

Turn the key on...pressure jumped to 20psi and pump shut off.

Turn the key on again....pressure jumped to 30psi and the pump shut off.

Turn the key on again...pressure was 40psi. This time I started it and fired right away.
Yep, something's leaking.

If you've never done the FPR or the pump, I'd do the FPR first, pump second.

Well, no, I'd do a tune up, then check it over the next 1,000 miles to see what the oil's doing (is it being diluted?) to see if it's a leaky injector; but at the age of the car, I'd bet FPR or pump.

(Since I've done injectors and FPR, I'm betting the pump on my wife's Cougar, Ruby Jean ... )

RwP
 

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Discussion Starter #12
Replaced the FPR last week.

Leaning toward the pump at this point.
 

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3 primes to get adequate fuel pressure definitely sounds like a fuel delivery issue. I can let my car sit a few weeks and the first prime is all it takes to fire it up. Sounds like a worn out pump for sure.

You can always bring it by my dad's shop like I mentioned in my last post.
 

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Replaced the FPR last week.

Leaning toward the pump at this point.
3 primes to get adequate fuel pressure definitely sounds like a fuel delivery issue. I can let my car sit a few weeks and the first prime is all it takes to fire it up. Sounds like a worn out pump for sure.

You can always bring it by my dad's shop like I mentioned in my last post.
Sounds like you've done a decent diagnosis (could still be a leaky injector), and sounds like a plan to get it fixed.

I'd plan on doing the fuel pump anyway if you drop the tank; that's the major portion of swapping the fuel pump, and it makes no sense to not go ahead and do it.

(I'd also make sure the fuel filter was replaced at the same time - the frame mounted one under the car, on the passenger side frame stub, just about right under the passenger front seat.)

RwP
 

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Yep, best to have a lift or at least get the whole car up on jackstands to do the pump. I'd advise against the full assemblies and just buy an upgraded Walbro 255 series pump for it.
 

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Yep, best to have a lift or at least get the whole car up on jackstands to do the pump. I'd advise against the full assemblies and just buy an upgraded Walbro 255 series pump for it.
What I'm planning on, since I'll have to get with my mechanic (I don't have facilities to lift the car up like that), is to pick up an old top hat out of the boneyard; rebuild it with a higher performance pump; and have the mechanic swap THAT into the car.

That's the plan anyway.

RwP
 

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Sounds like a fuel pump check valve issue. I believe the system is different on our cars and have them built into the fuel pump assembly. The check valve is what keeps the fuel from flowing back into the tank and allows for a quick prime. You might want to check into replacing the whole unit and if you want to upgrade to a bigger pump you could do it with a new assembly.
 

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Sounds like a fuel pump check valve issue. I believe the system is different on our cars and have them built into the fuel pump assembly. The check valve is what keeps the fuel from flowing back into the tank and allows for a quick prime. You might want to check into replacing the whole unit and if you want to upgrade to a bigger pump you could do it with a new assembly.
You can put the bigger pump on the same stock assembly. The upgrade pumps aren't physically larger by much or if it all.
 

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You can put the bigger pump on the same stock assembly. The upgrade pumps aren't physically larger by much or if it all.
Yeah you can. I'm not saying it won't fit the stock assembly but your problem may persist if there is a problem with the old assembly. If a check valve is not keeping the fuel from draining into the tank, a new pump isn t going to correct anything. As much time and effort as it takes, if you're doing this project at home without a lift, why put a used assembly back in with a new pump IF you're having an issue like this. I would replace it with a new assembly and eliminate any possible in tank issues. I'm not telling anyone what to do here but sharing my opinion of a possible solution. Who knows maybe the new pump will correct the issue for a while and put him back in the same place later then he begins looking in other places thinking he solved the in tank issue. Again, just my opinions and thoughts.
 
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