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Q: po740 code on 1999 Honda Civic

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
just put used trans in
No car image 94a1663db56199c5353592009e34aaa51078a2469bed068bb8d6f0ba43accf97
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What was the reason for A/T replacement(code(s) for original trans failure?)Was TCM 'cleared' after replacement or could that be a code from before? A little more info would help.
sORRY ABOUT THAT car had 137,000 no ck eng lites no problem driving or shifting again this is my daughters car she drove about 2 mi and that was it says rpms were moving but not car,she parked it got ride to work and went over to ck it out got in car drove fine up to corner then nothing call my mech.he made around block stoped waited made to shop put comp on no codes advised me to get a used trans located one he put it in was driving nice around neighborhood she drove on high way abot 20 mi ck eng light came on put comp on po740 came up
The shop that installed it needs to verify that it's the correct trans. for your car. The Dx &Lx models(non V-TEC engine) have a different trans than the Ex model(V-TEC engine).Let the shop know they can reference 'Honda Service News' , April 2004 page 4 , for better explanation. The differences are mainly internal , so a visual comparison is not reliable , except for a washer under the mainshaft speed sensor if it's for the Dx or Lx , no washer for the Ex model.......hope this helps. IF they are SURE it is correct trans (May be worth having Honda dealer verify independently?), then reply and I will post some diagnostic tips if needed. Good luck!
Premature failure due to getting incorrect signal from mainshaft speed sensor.Trans. controled based on inputs from sensors , if it's getting the wrong signal , it's not going to control the pressures correctly.Other than that, honda does not 'detail' the long or short term effects , it just states to install the correct trans. That's just from the engineering 'technical' point of view , who knows , it may go for 50K , just with the check engine light on constantly. The only problem with that , is that you won't know when another problem occurs until it may be to late. Maybe buy a cheap 'code reader' and make a habit of scanning once a month to monitor it?
Look for any other codes , besides p0740 , and get them diagnosed and repaired as needed.Good luck.
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