4l80e p1810 help

Hey all. My truck has a P1810 DTC which is for TFP switch malfunction. Has had this since I put this motor/trans in. I took it to my trans guy to hook up his scanner and drove it and he said the switch is functioning properly.

Symptoms: Between ~40-55mph with light throttle the TC will lock-unlock rapidly until I change throttle position. Also, it stumbles and chokes a lot when at low speeds (like parking) when the CE light is on but acts fine when the light is off.

Notes:
I had Nelson change my lockup mph in 4th to 40mph.
Occasionally the TC wont lockup above 55mph either.
Occasionally the TC works perfect at all speeds.
The TC is a 9.5" RevMax 2800rpm stall converter.
The pressure switch was replaced when the trans was installed 3/2010.

My trans guy said I should have Nelson just remove the code from the computer altogether.
What do you think?!

Quote:

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Originally Posted by flattopwill

Hey all. My truck has a P1810 DTC which is for TFP switch malfunction. Has had this since I put this motor/trans in. I took it to my trans guy to hook up his scanner and drove it and he said the switch is functioning properly.

Symptoms: Between ~40-55mph with light throttle the TC will lock-unlock rapidly until I change throttle position. Also, it stumbles and chokes a lot when at low speeds (like parking) when the CE light is on but acts fine when the light is off.

Notes:
I had Nelson change my lockup mph in 4th to 40mph.
Occasionally the TC wont lockup above 55mph either.
Occasionally the TC works perfect at all speeds.
The TC is a 9.5" RevMax 2800rpm stall converter.
The pressure switch was replaced when the trans was installed 3/2010.

My trans guy said I should have Nelson just remove the code from the computer altogether.
What do you think?!

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How does the truck run with the code cleared? If it runs just fine, I don't see why that would be an issue... although I feel there is a mechanical issue somewhere.

It sounds to me like one of 2 things. Thas caused by if u start truck and quickly put it in gear. Not alowing the PCM to read proper gear range. Very common prob with 80e. Or the tcp switch has went bad. Have ran into this a few times. Clear codes and try waiting min before put in gear. If don't fix then replace switch. Also with this code ur tranny will b at max line pressure causing harsh shifts and can blow trans seals in drums.

Quote:

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Originally Posted by pl4yboy

How does the truck run with the code cleared? If it runs just fine, I don't see why that would be an issue... although I feel there is a mechanical issue somewhere.

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The TC will still have an issue with the MIL off but I know that the code can be tripped multiple times before the MIL is turned on. Therefore, I dont know if it messes up before the code is tripped because I'm not sure when/what conditions it is under when it trips the code. But, with the MIL off it does not stumble or choke while parking.

Quote:

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Originally Posted by LQ9_Z71

It sounds to me like one of 2 things. Thas caused by if u start truck and quickly put it in gear. Not alowing the PCM to read proper gear range. Very common prob with 80e. Or the tcp switch has went bad. Have ran into this a few times. Clear codes and try waiting min before put in gear. If don't fix then replace switch. Also with this code ur tranny will b at max line pressure causing harsh shifts and can blow trans seals in drums.

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Also, I read that this problem can be intensified when it sits for a while and there is torque converter drain back. I wonder if there is a flow/hydraulic pressure issue in my transmission/torque converter?

On a side note, with his scanner hooked up we tried to command TCC lockup but there wasnt an option to do so in the Special Tests. Whats up? Is this something to do with his scanner or my PCM?

Tonight, it wouldn't lock the torque converter in 4th. It would lock/unlock rapidly but then quit. If I pulled the shifter down into D3 it would lock the converter no problem and would stay locked until I shifted into D4 then it would unlock.