OEM code AFTER new trans install!!

[tjcox]

I have a 98 Honda Civic EX that failed emissions with codes P0700 and P0740. After calling around to different dealerships, I was told that I would more likely than not... need a new transmission . So, I just had (as of in 2 hours ago) a new transmission installed. As I was coming home (65 miles) the check engine light came on again and the same codes are showing up . The trans seems to be shifting just fine and runs great.

So how do I get these codes to go away long enough to pass emisisons and get my tag (that expired in December)??

Any help would be appreciated!! Before I go

[honda_luvr_2000]

take it back to the place that put the trans in and have them diagnose it again. i hope u didn't just take the word over the phone and have the trans put in w/o them actually diagnosing it first. if they did diag and then replace the trans, then they owe u another free diag since they obviously didn't fix the problem u brought it in for. if u had this done at a dealership then they should also give u a rental until they do fix it, but not all dealerships r created equal.

-edit:
i just did sum quick research and w/ that code coming right back then u may have one of a few problems all of which they should pay for to fix since they didn't fix it correctly.
1) they could have put a trans for an LX or DX in, instead of one for an EX (they look identical but they aren't)
2) the torque converter o-ring could be damaged or missing (torque converter should have come w/ replacement trans and thus not damaged/forgotten by them but whomever rebuilt the trans)
3) the lock-up control solenoid valve assembly could be faulty (now one of two things could have happened here, if the trans was a rebuild from an aftermarket company then solenoid may have been swapped from u'r trans to the new one and was bad to start w/, or if the trans was a rebuild from honda then the solenoid was new and defective)

my guess is since u say it's shifting fine and everything driving-wise seems normal, then the problem is probably 1 or 3 and not 2. if the o-ring was missing then it wouldn't be shifting right because it would have an internal leak and or problems you would notice.

if you had this done at the dealership, then they should foot the costs to figure out wut went wrong and fix it.

[240slider]

the codes that you are getting usually mean that you need a new tranny ,p0740 is for the torque converter failure.and p0700 is the code indicating that there is a transmission problem. also if the place that installed your new transmission did not flush the cooler lines that can cause problems with the new unit .