Oh boy... Little bit of a rant here but also I still need help. So a while back my truck started to stall at stops out of nowhere. Doesn't do it all the time, only sometimes and if i switch from Drive back into Park it acts fine, but going back into Drive it tries to stall if I don't gas it. It also has stalled on me a couple times while Reversing and turning the wheel to pull out of a parking space.

So first I took it to a shop myself and they used a $15,000 diagnostic scanner that can run the truck itself and do remote tests on it. Ran it twice.They said it was throwing anti-theft codes, no misfires or anything else. but I don't think the guy knew how to use it right. Then a couple days later I hook up my OBD2 scanner and now I have a new code P1740.... torque converter. So I stopped driving the truck and I had a friend take it to a different tranny shop to get it diagnosed because I work 70 hours a week and don't have time. This shop said it was throwing all kinds of codes and misfire codes, but they didn't specify what exact codes. I never saw any misfire codes ever. It had two codes. Cataylic converter code p0420 because they are both hollowed out, and the code P1740. How do misfire codes randomly appear in a couple days?

Then without my consent they change all 8 spark plugs, boots, and the fuel filter and charge me $250. I had done all of that like 6 months ago. They put an offbrand fuel filter on it, I haven't pulled spark plugs to see if they are motorcraft brand or not, but Im sure they arent, Just really pisses me off. Doesn't run any better than it did, but It hasn't stalled again yet, but I will wait like a month before I conclude it is fixed. So anyways when I went to pick the truck up today I hooked my OBD2 scanner back up and now magically there is a misfire code for cyclinder 1.... A code I've never seen in my life and I've had this truck for almost 7 years now. I got it to go away after resetting the PCM, but the P1740 code and the P0420 code is gone also. So I'm not sure how codes are issued adn stored, but how did they erase them and will they come back?

 

Well both of you are at fault not knowing what is going on with the codes.
1. You cannot fix any trouble by clearing codes. They set for a reason. The system never makes a mistake.
2. The cat codes will set with empty cat converter housings because the rear Ox sensors has detected the malfunction of the converters. After a while the codes for this may clear because the codes serve no other purpose as they don't affect engine operation, only Emissions test failures.
3.The 1740 code is a transmission Torque Converter Clutch solenoid failure.
4. Don't know what your misfire will turn out to be at this time Not enough info.
I hope I helped you get back on the ground with the problem and not trying to antagonize you.over it.
You came to ask, I helped you with most of all you needed to know.
Good luck.

 

Solved! Stalling at stops was caused by a loosely connected relay in engine compartment. Relay 301. That's the fuel pump relay.

The couple of shops I took it to blamed torque converter and said it needed a transmission rebuild LMAO. Glad I stuck with diagnosing and finally found the problem. I guess it was in a position where it would be fully seated and then sometimes lose connection or it was slowly going bad and then it would starve itself of fuel, thus stalling the engine out. Hope this helps some people in the future cause that was a PINA trying to figure out.