**2005 Expedition 5.4L V8 Throwing Codes P1740-FF and P1744-FF – Need Help

[johndoe406]

Hey everyone,

I’m having an issue with my 2005 Ford Expedition 5.4L V8, and I'm hoping someone here might be able to point me in the right direction.

The vehicle is throwing two codes: **P1740-FF** and **P1744-FF**. Both are related to the torque converter clutch system, specifically indicating “torque converter clutch system performance or mechanically stuck off.”

Here’s what happened: I was driving one day, and suddenly, when I hit about 20 miles an hour, it started acting like it was in neutral. The RPMs would go up, but there was no movement. First, second, and reverse gears still work fine, but in drive, it just revs up with no power transfer.

Additionally, I’ve noticed that sometimes when I put it in park, the vehicle won’t start unless I shift it into neutral. I'm not sure if this points to a possible switch issue or something more serious.

Has anyone experienced something similar? Could this be a simple loose wire, or is it likely a more complex problem? Any advice on troubleshooting steps would be greatly appreciated.

Thanks in advance for your help!

 

[whtbronco]

Sounds like multiple issues, but maybe not. The neutral safety could have an issue since it will start in neutral, but sometimes not in park. I'd go after the P1740 and P1744 codes first.

What's the trans fluid age, condition and is it full, that's what I would check first. Here's the list of likely culprits I found.

Low transmission fluid level
Dirty transmission fluid
Faulty torque converter clutch solenoid valve
Torque converter clutch solenoid valve harness or connectors
Torque converter clutch solenoid valve circuit is open or shorted
Transmission internal mechanical problem

Since I can't drain the torque converters anymore I change half the trans fluid every 2yrs or 25k miles and the filter along with half the fluid every 4yrs or 50k miles whichever comes first. To me it's cheap insurance, or at least I feel better about it.