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Q: I'm having problems with code po740

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Hey, I have 2002 Honda Civic 1.7 that I purchased with a bad transmission, I dropped that tramission and put a used one, after I installed the transmission and ran the car check engine light came on and code was po740 torque converter solenoid. The transmission shifted perfectly fine, So I did some research I change the solenoid and ran the car the check engine light came back on, so I checked my wiring and continuity from the solenoid connector to the pcm and the continuity was good, I drain the fluid and put the dealers transmission fluid ran the car again and light came right back againg. So I took the car to a mechanic and explain everything that I did to the car, so we came to the conclusion that it was the torque converter so I dropped the transmission againg and went and got another one since it still had warranty. I installed the other transmission with a new torque converter, took the car for a spin and drove for like 3 miles and the check engine came on with the same code.

My car has 171456 miles.
My car has an automatic transmission.

Hi there. In order to be able to give you more exact information I would need to know whether or not the vehicle is equipped with the CVT transmission. It sounds like you have the regular transmission in your vehicle. If the solenoid is new then you either have a wiring or computer issue. I would definitely make sure that you have the right transmission in the vehicle. If the year is not the correct one then the reading from the solenoid will be incorrect. If it is the right transmission then the wiring to the transmission needs to be checked for any loose or pinched wires. If those are fine then the wiring to the computer and the resistance and the signal from the computer need to be checked. This type of problem on your vehicle is best diagnosed by a transmission specialist.

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