I'm having a lot of trouble with transmission slipping. Codes are P0740, P1739, P0730 and P0453. Of course, all a deep mystery to me. Do I need to limp to the junk yard or can I salvage "old faithful"?
Mackie (99 Accord, EX, V6, 213000 miles)

 

P0740 means TCU detected excess slippage when torque converter should be in Lock-Up. This is a hydraulic fault not easily remedied. There are inlet screens on the LU solenoids that might get blocked, but thats about it.

P0730 is "Fails to shift between 1-2, 1-2-3, 1-2-4, 1-3-4, 2-3-4 gears only"

P1739 is "3rd clutch pressure switch circuit" based on a post at another site.

P0453 is evaporative emissions problem not associated w/ trans problems.

Make sure fluid level is good and fluid is not burnt smelling. If so, drain and replace 3 times w/ Honda ATF.

This era of Accord V6's were problematic. You may indeed be looking at trans replacement w/ used or rebuilt, or to the knacker yard.

good luck

 

Many Thanks! My worst fears confirmed.

 

With that mileage you did good especially the Accord. Take it to a good transmission shop and have them check it for you, will cost about $40, they will confirm if the problem is internal or external. But prepare for the worse, check your local junk yards, of car-parts.com, Honda auto has many issues with auto trans so they're expensive even for a good used one.