Engine fine for 25 min, then sputters runs rough and stalls

Hi Everyone,

Took her out of storage a couple months ago, though only a drive or two since. For the last few years, (when first out of storage), she starts right away and drives fine for 25 to 35 minutes and then sputters, runs rough and sometimes would stall. I would add fresh fuel and she would be fine after. Thus figured it was stale fuel. 
This time out of storage she did the same, but after new fuel, still running rough after 25 minutes or so and stalls. Previously putting petal to floor would usually have her start right up again - not this time, she would flood. After sitting for 15 to 35 minutes (cooling down) she would start, one time run fine, another run rough for a minute or two and then run smoother. 

Also, the key doesn't always crank the motor. Seems when she is hot some times, engine won't crank w/key. I had to jump the solenoid to start the car. I read voltage and the start wire to solenoid is 11 volts with battery reading 12.3V. 

I pulled codes (KOEO): 41, 42, 64 and 65.

At first I thought it may be the ignition in the column.

Though after doing a lot of searching, I think it is the TFI. Going from what I read in this thread:
https://turbotbird.com/thread-engine-shu...ht=code+42 

Hi Everyone,

Took her out of storage a couple months ago, though only a drive or two since. For the last few years, (when first out of storage), she starts right away and drives fine for 25 to 35 minutes and then sputters, runs rough and sometimes would stall. I would add fresh fuel and she would be fine after. Thus figured it was stale fuel. 
This time out of storage she did the same, but after new fuel, still running rough after 25 minutes or so and stalls. Previously putting petal to floor would usually have her start right up again - not this time, she would flood. After sitting for 15 to 35 minutes (cooling down) she would start, one time run fine, another run rough for a minute or two and then run smoother. 

Also, the key doesn't always crank the motor. Seems when she is hot some times, engine won't crank w/key. I had to jump the solenoid to start the car. I read voltage and the start wire to solenoid is 11 volts with battery reading 12.3V. 

I pulled codes (KOEO): 41, 42, 64 and 65.

At first I thought it may be the ignition in the column.

Though after doing a lot of searching, I think it is the TFI. Going from what I read in this thread:
https://turbotbird.com/thread-engine-shu...ht=code+42 

Automatic or 5-speed?

This is important. If a 5-speed, your cranking problem could at least partly be the neutral safety switch. This little bugger sits on the clutch pedal and is a B-I-T-C-H to access. You have to contort your upper body to lie on the driver's floor on your back (I laid my lower body on a couple of milk crates). There are two wires that, by a connector, provide the positive connection for this circuit.The switch is a toothed shaft that, by a couple of plastic locks, actuates the switch contacts. When you first install a new one you are told not to try and adjust it--put your foot on the clutch pedal and press it firmly to the floor, this will automatically adjust it properly. (Yeah, and most of the time that's true.)

I had jumpered those two wires when the switch on my TC broke a few years ago. I should have left it that way--but twice the relay seized and the car would not stop cranking, even without the key in the ignition. I installed a new switch hoping that would solve the problem--but the issue is that the fault occurs AFTER the neutral safety switch is actuated, so a new one didn't help. When the temperature here in Phoenix no longer resembles the temperature of the Sun (KIDDING), I'm going to bypass it again. The problem is that sometimes I have to stomp on the clutch pedal to get the car to start.

As for the stalling issue: have you checked the fuel pump for how much it's putting out? There's lots of stuff on that in the older posts. There's a Schrader valve on the fuel rail, connect a Fuel Injection Pump Tester to it and take several readings. Again, off the top of my head I can't tell you what the numbers should be...but when I was having similar issues years ago, that test helped me eliminate the fuel pump (it was the throttle position sensor [TPS]).

She is a 5 speed. I thought of that clutch switch. I used alligator clips on each side of the switch and then when she wouldn't start, I connected the clips at the other end to close the circuit. This way when the two clips are not connected the car works as designed and when connected bypasses the clutch switch. Last year when the motor wouldn't crank, I connected the clips and she would start. This year when I connected them, motor wouldn't crank. I will have to make sure the clips are still connected at the switch. Thanks for mentioning it!

I will check the connection and update shortly.

She is a 5 speed. I thought of that clutch switch. I used alligator clips on each side of the switch and then when she wouldn't start, I connected the clips at the other end to close the circuit. This way when the two clips are not connected the car works as designed and when connected bypasses the clutch switch. Last year when the motor wouldn't crank, I connected the clips and she would start. This year when I connected them, motor wouldn't crank. I will have to make sure the clips are still connected at the switch. Thanks for mentioning it!

I will check the connection and update shortly.

That's actually a genius idea.

Instead of messing with the wiring for a more permanent but difficult solution (to implement), I like yours. Just use tiny alligator clips if it fails.

Thanks for that.