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Discussion Starter #1
'96 4.6 v8. ~50k miles. During quick stops she would 'sputter' some when trying to start, if I give it some gas, she seems to fire right up. This has been isolated to quick stops, but has happened a few times after long stops. It doesn't seem to be electrical or starter, it spins just fine, but kind of coughs. I'm thinking fuel delivery.
So my plan is to check out fuel pressure and leak down to make sure the fuel system holds pressure. Any other ideas?? Thanks.
 

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Try turning the key to on and listen for the fuel pump to kick and prime the system, then try to start and see what happens.

Joe
 

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Discussion Starter #3
So I've been paying more attention. If I remember to let the pump pressurize it seem to start fine. Also, the few times it did sputter, I turned the key off, then let the pump pressurize and it fired right up.
Does that tell you anything, Joe?
 

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Yes. That sounds like a weak fuel pump to me or a leaky regulator which isn't letting it hold pressure. So when you tested the pressure how long did it hold pressure? That is important. If the fuel pressure is dropping within minutes, you definitely have a worn out pump or bad regulator. But I'm betting on fuel pump.

Was fuel filter changed recently (last 50k miles)? If not then it could be a restriction. I'd start off by changing the fuel filter, since that's quite literally the easiest and cheapest job ever.
 

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Was fuel filter changed recently (last 50k miles)? If not then it could be a restriction. I'd start off by changing the fuel filter, since that's quite literally the easiest and cheapest job ever.
That, and logically the fuel pump should still be fine if the car only has 50k on it.

It this ends up being a red herring you might have problem with IAC. My car would have issues starting similar-ish to yours and occasionally would just cut out all together when idling. Replaced the IAC (with Motorcraft I believe...don't get el cheapo parts stores brand) and have not had a problem since.
 

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Discussion Starter #6
I've been fixing other stuff and haven't pressure tested yet, hopefully this weekend.
 

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Discussion Starter #7
Finally had change to test this out. Fuel pressure was low from the beginning. I let it prime couple times and came up to about 30 PSI. Then started and it seemed to hold pretty well ~29-30 psi. Opening the throttle some the pressure would increase slightly ~1-2 psi. When shut down, it held at 29 psi, it was a good 10 min and it only dropped ~1psi. I'm going to start with the regulator and hope it's the cheap and easier fix. Thanks.
 

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Discussion Starter #8
Replaced the regulator today. Went the extra mile and borrow the pressure gauge again. Initially it seemed the pressure was still a little low. Started her and pressure held ~30 psi and increased with throttle. Ran for a while, shut down and held pressure ~35 psi. Could be the fix. I'll monitor it and see if those hard starts happen again. It seems more responsive now also, could be placebo.
 
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