Hyundai Repair: P0734 Improper 4th gear ratio, range switch, work car


Question
What could i do to fix this without spending alot of money? I've already put a pulse generator on it about 30k ago, but it still surges and rpms shoots up. Then it will kick out back to overdrive. It does this everyday repeated going to work that is 65 miles away. Now it sets in the driveway, want go in reverse and it seemed like when i was bringing it home that it wouldnt shitf out of 2nd gear. This is my work car please help.

Answer
Most likely, you won't be able to fix this without spending a large amount of money.  In a very high percentage of cases, these symptoms will be only be resolved by replacing or overhauling the transmission.

There are, however, two simpler things which could potentially lead to these symptoms.  The fluid could be low.  If it is, it's important not only to fill it, but also to find the leak and fix it.  Or there could be an issue with the range switch or its adjustment.  I've seen this cause similar symptoms, but considering there are no trouble codes related to the range switch, it's a very unlikely problem.

You could continue to drive the vehicle (at least for the time being) with the shifter in 3rd instead of D (or with the overdrive turned off) and plan your driving and parking so you won't need to back up.  By the same token, since you've already got two problems, the potential is present that you'll have more transmission problems within a reasonably short amount of time.

If you do need to replace or overhaul the transmission, I'd recommend investigating having a factory remanufactured transmission installed.  Hyundai prices these very competitively, so you may be able to have one of these installed cheaper than you can get an overhaul or cheaper than you can buy another company's rebuilt.