Engine High rpm miss

[Pinellas50]

Also, when it does it, it’s more like it loses power, not bouncing off a rev limiter. It has to crank for a couple seconds to start but it’s always done that. Starts the same hot or cold.

Have you tested fuel pressure yet? What you describe is a symptom of a warn out fuel pump.

 

[claypoolxx]

I haven't tested fuel pressure yet. I am going to take a long drive this weekend and see if its truly gone away. If there's still an issue I'll have to borrow a gauge that's long enough to read while driving. I plan on changing the fuel pump. I have a walbro 155 waiting, but I don't drive the car much and the tank is still close to full, so I am trying to eliminate anything else if I can. Right now I haven't spent any extra money other than on the TFI, which I wouldn't mind have a backup in the glovebox anyway. Hopefully by Sunday I'll have a concrete answer.

 

[claypoolxx]

First off, Happy Father's day to all the Stangnet dads. I'm fairly certain my issue was/is the TFI. I drove it for about a half hour and it never cut out at all while at WOT. However about 10 minutes into my drive cruising at about 40 in 4th gear the car shut off. Seems like that is a common TFI symptom.

Also when I started my drive it was at about 7/8th of a tank. I didn't stare at the gauge, but I noticed a few minutes after the car shut off it was one mark below half a tank. Theres only about 55 miles on the tank with about a 1/3 of a tank left. It has been a very hard 55 miles with many full throttle blasts. Is the fuel sender of gauge known to be funky?

I ordered the motorcraft one from rock auto. It came in a motorcraft box but has no markings on the unit itself. Does anyone have any advice on where to get the next one?

 

[Mustang5L5]

The fuel senders on these cars have a habit of reading full for a while (tricking you into thinking your are achieving stellar fuel economy) and then dropping like a rock to “catch up”. I’m not sure I would count on it to be too proportional.

Even my 03 GT i bought new did this.

 

[90sickfox]

My advise for TFIs is the junk yard. Grab as many as you can find. The Motorcraft factory ones were good and lasted a very long time. My TFI came from advance auto 14 years ago. It's installed on a billet MSD distributor. No issues but I've heard quality has gone way down since then.