P0747 - Check Transmission
 

When I started my commute home tonight I decided to try out the Sport shift mode to see if I could get better mileage than what it is doing on its own (not high hopes, but have to try something). I shifted to S and started out - the engine got to around 3-4K and then upshifted, but with a lurch. That didn't sound right. I tried hitting a paddle to upshift again and nothing so I switched to D. It then seemed to continue in a bad gear and lurching on most of the shifts.

As I drove it seemed that it would lurch on an upshift from something like 2 to 3 and then it would lurch twice downshifting as I came to a stop. It also acted like it was in a very low gear when coming to a stop with lots of engine braking. After a few starts and stops a P0747 code showed up in diagnostics and the message was "the transmission may operate in lower gears and shift abruptly until you see your dealer. please schedule an appointment as soon as possible"

I had a highway commute home so I decided to just drive home and call the dealer tomorrow morning - it was doing about 3K on the tach at 60-65 and behaving reasonably other than feeling like it was in 3rd or 4th instead of 5th so I headed home. (FWIW, mileage was about 20MPG which was not bad considering I don't get much better than that normally.)

Grrr... 1400 miles and ready for????

The only up-side is that I'm hoping that whatever is wrong with it has also been causing my rather disappointing gas mileage so far before it went completely clunky.

That code means your AT clutch pressure control solenoid valve A is stuck on. Could be as simple as replacing the ATF but may be as bad as replacing the transmission. Most likely they will have to replace the valve. Good luck and let us know what the outcome is.

Damn, that blows.

I was disappointed to learn that sport mode tops out in 4th gear, and won't shift into 5th even at highway speeds (though you can force it into 5th manually but then you're into full manual mode). So I wouldn't expect it to help MPG if you do a lot of highway driving. On my last car, sport mode affected upshifts and downshifts, and would hold gears in corners, but still went into 5th. I used it all the time and didn't notice a gas mileage hit. Then again, my driving is biased to highway cruising where the car quickly hops into 5th gear regardless of mode. It's a pity the RDX sport mode locks out 5th gear.

Good luck on the trans issue -- I hope the fix is quick and painless. If they can access that valve through the bottom pan, then it should be fairly easy to address the problem. Keep us posted.

I was hoping that I could use it to hold lower gears more until I get to speed. One of the things I've observed is that when I need a little bit of acceleration while cruising it appears to spool up the turbo instead of downshifting - that may feel more "comfy", but it seems to eat more gas than just downshifting. Anyway, it was just the kernel of a theory and I didn't get more than 30 feet on trying it out before "CLUNK".

Also, I need to try it out in the twisties again with S mode - there I was having serious "you're in the wrong gear again dude" problems with regular Drive. Someone here mentioned that it downshifts when you brake into a corner, but my experience was that when I came off the brakes onto the gas it was caught by surprise. I did put it in S mode briefly while I was doing my twisty run, but left it in non-manual mode and the mileage went up by a couple of MPG, but the gear selection wasn't really much better for handling. I didn't want to try full manual there because the paddles are never accessible when the road is too curvy (dang hi-tech pretend-boy-racer ergonomics)...

In any case, I'm calling around to dealers in the SF Bay Area - if anyone has a recommendation on the best service I'm all ears...

It's at Serramonte Acura. They were going to make me wait, but the service consultant took my P0747 code back into the service bay and when she returned she immediately set me up with a loaner car(*). I hope that isn't a bad sign. :(

I had a little bit of trouble with her attitude. She kept talking to me like "Oh you poor child, a problem with your car? This beautiful car right here? Oh, that is so surprising, you poor thing." I imagine it might make some people feel comforted with thinking "Yeah, I thought that was kind of odd", but it felt more like "I'm pretending that we never get cars with problems so that you think Acura is a great company" and it really started grating on my nerves after a very short while. I kind of felt like saying "listen, cut the crap, let's get this car in the queue for service", but didn't want to rain on her little show. It wasn't so much "unprofessional" as it was cloying.

(*) Loaner is a white RDX Tech with black interior, 3200 miles on it and they gave me a non-remote key - grrr...

Just got the call from the dealer - it seems my clutch pressure control solenoid valve needs to be replaced. Who would have guessed? Oh, wait, you did... :thumbsup:

The part is on order so they'll have the car for a couple of days waiting for it...

well thats good to hear. Much better than having to replace your transmission!

Sasair's the RDX guru. :toocool:

No doubt, sasair's the man!

flare - did you get your solenoid valve replaced?

Once again, owners are two steps ahead of the dealers, and the value of this forum is proven.

It's on order, supposed to arrive tomorrow (Tuesday)...

Just got my car back today - woohoo! It took them a couple of days to install the part after they got it. When I picked it up it had a "77" code from the AWD system in the diagnostic messages which sounded scary, but the voice said that the remedy was to pull over and power cycle the car and see if it went away. Since I didn't have any warning lights I'm guessing it was a temporary problem they had during one of the test drives, but it would be nice if they'd either clear it if they know that it's not an issue or let me know that it happened...

Hmm... One should assume that you could drive the car home in S mode, without any problems. I played with it here and there, but never started the car in S mode and went from there. But I've been meaning to check it out myself (start to finish) Keep us posted.

Yea, did ya notice that the st. wheel is contoured like your driving a plane? That's why the BMW X3 has those aweful orange lights. My point is though, darn, They messed up the ergonomics! Have you tried to answer the phone on a curvey road, or while turning? same thing with the paddles...where are they when you need 'em? I think the guy that thought that up never drove the test model. I'd rather have the call/answer phone button on the panel somewhere at the push of a button...NOT on the steering wheel (diddo on the paddle shifters).

Many of the things on the steering wheel are not intended to be accessed while turning a corner so it isn't much of an issue where the buttons are when the wheel isn't in the home position.

I think you could probably say the same thing about the shift paddles, though. Ideally you would know what gear to be in before you get to the corner. With a manual car I'm usually pretty well trained as to gear selection by the time I've got a couple hundred miles on the car. With this car (it's the first AT I've ever owned), I'm in the dark so I sometimes want to change my mind during a corner. The solution is probably to drive more around the city in S-Manual mode until I get an idea of what the gearing is like before I try doing my own shifts on a twisty road...

this is old, but anyone having similar problems with their trans?

Thought it was weird how high the rpm's are in S mode on highway, but seems it is normal.

My car is starting to feel off at cruising speeds with gentle acceleration. It feels like the converter is not engaging all the way and I am getting some slipping.

When I hammer it it feels connected, just at light throttle it seems to make more noise that speed.

BTW have done all fluid changes. 3 times with 125K on clock. Last one was a few thousand miles ago.

Do you have the part number by any chance? Have the same code for my 08 Acura TL typs
 

do you know the part number by any chance? I have the same code for my
08 Acura TL Type S automatic