Hello,

I have a 2000 Honda Civic Ex. It turns out the previous owner put a Dx trans in it. The car runs and shifts great. I just got 32 mpg on my last tank of gas with mostly highway driving. It has nice firm shifts in the lower gears around town. There are no strange downshifts or slipping at highway speed up hills. I can't tell if the torque converter is locking up or not, because I don't know what to look for.

I am getting a p0740 code from the scanner at Advance Auto. The scanner at Orielly shows p0700 p0740 and p0706. If I reset the codes, the CEL comes back on after about 10 miles of highway driving. I changed out the lock out solenoid and have changed the fluid twice. The ECU is a new/ used one that fixed a idle air control problem. When I had the trans out to do the rear main seal I noticed a non matching Vin on the trans. I didn't think much of it at the time. The trans has vin# 1HGEJ6673YL005957.

I have been reading that the DX trans isn't compatible with the EX motor or ECU and will throw a p0740 code. I don't mind having the code light on, but don't want to destroy the trans. If I run this setup will I burn up the transmission?

 

Only time will tell.

 

Install the correct transmission.

 

Thanks for the replies. I am hoping to get some useful information on which to base my decision. Nothing needs to happen right away. It looks like I can drive the car around the city without going on the highway and damaging the higher gears or TC. The CEL light doesn't come on until I go out on the highway.

My options are: Run it blindly and hope the wife and kids don't break down in a bad neighborhood. Or I can gather some facts and opinions about running the mismatched motor and trans. Or I can find a good used transmission and line up a buyer for the old transmission while its still in the car. That way I can prove the transmission is in good working condition.

All are good options. Of course I don't want to swap the transmission, but I will do it if I have to. Since I have already had it out once to do the rear main seal, I would like to put some miles on the car before adding extra time and expense.

 

so go find the right trans, run this one till it blows. d series a/t are only worth around 100 bucks used.