Andydana

A few weeks ago my 08 RDX would not shift out of 2nd while in traffic on the highway. Check engine and transmission light came on as well. Had it towed to a transmission shop, the codes were for a 3rd gear pressure switch so I replaced it and everything was fine for about two weeks. Then it did it to me again, this time I was also in highway traffic. I was able to put it in sport made and shift into 4th and just skip 3rd. Never got a code and only does this on occasion. I am thinking the transmission is heating up and I have a bad 3rd gear clutch so in need a new transmission. Anyone have any experience with this issue? Could it be a throttle positioning sensor? I drove the car thru traffic for 2hrs yesterday and didn't have any problems and it was 93 degrees out.

thoiboi

Did you replace the fluid when you did the sensor? If not, when was the last time it was replaced?

Andydana

Yes did a drain and fill on the trans when I did the sensor. I bought the car at 115,000 two years ago. It has 136k now. I know the previous owner must have had the radiator replaced because the trans cooler line rotted out and there must have been mixing of fluid but the trans fluid has always looked fine since I owned it. I'm assuming they also would have changed the fluid after they fixed the trans cooler, because both fluids look great.

thoiboi

What kind of fluid did they use

Andydana

Good question. I know Acura doesn't use the Z1 anymore and the original fluid when I purchased the car looked Carmel not red so I'm guessing it was changed from the Z1 at some point to the new fluid they are using maybe DPSF? Not sure what my mechanic used he's a transmission guy so I would assume it was appropriate, but I did notice it was a little more on the pink side after, so I'm assuming he added a red fluid that's all I know.

01acls

Probably not a clutch problem. If it was you should be getting flares.

It could be a torque converter valve sticking. You could also try replacing the shift solenoids A, B, and C.

Before you change anymore parts you should try the stop n go to purge the torque converter and hope the filters catch the debris that will be dislodged.

Simply start from a dead stop and accelerate briskly so you hear the torque converter spool up. Do this in first gear and don't let the car shift into second gear. So excelerate fast enough to raise the front end, maybe half to three-quarter throttle. Do the stop n go for ten minutes.

After the stop n go check the fluid condition/color. If it's burnt or dirty then change the ATF fluid (1x3) and do the stop n go again. Rinse n repeat until the ATF is like new.

If your problem persists after the stop n go/1x3 then change the three solenoids.

01acls

When doing the stop n go you only need to excelerate for 20/30 yards.

Andydana

If there is a bad Solenoid wouldn't it throw a code immediately?

01acls

There are different degrees of bad. You don't necessarily have a bad part. You may have a lazy part that's still working but not reacting as it should. A part that's worn or sticking just enough to cause problems intermittently or under a specific circumstance. Not every problem will throw a code immediately or at all.

Andydana

Also it's not that the trans doesn't shift out of 2nd it's that it doesn't engage into 3rd it acts as if it is in neutral.

01acls

That's not what your original post said. So it shifts from 2nd into 3rd but flares in the 3rd gear?

Andydana

Good point 01 acls . I am starting to think if it was an internal trans problem it would be more constant right? And especially when it gets hot. The fact that I drove it yesterday in the 93 degree heat, in traffic, for two hours and it was shifting through all the gears fine makes me feel like it would be electronic.

Andydana

Correct it shifts out of 2nd and acts as if it is in neutral instead of engaging 3rd. When it happened 2 weeks ago I was able to put the trans in sport mode and paddle shift it into 4th and 5th no problem but couldn't get it to engage 3rd. Woke up the next morning and the car drove fine shifted through all the gears no problem.

01acls

That would seem like a debris problem. I would still do the stop n go given the mileage on your car and since it's acting up or it have been acting up. You have nothing to lose and a lot to gain. It's only going to cost you a gallon of gas and 10 minutes.

Andydana

Thanks 01acls I will try that. I don't know too much about transmissions. I just know when there is something not normal. I did notice the issue this spring but it always came back into it after I stopped and started again. Sometimes I didn't even have to stop it would just rev up but then engage.

Andydana

The trans also appears to be a bit over full. When cold I checked it and it is a little bit above the top dot that's marked "hot" on the dipstick.

01acls

Ahh additional relevant info... Great?!

To you and anyone posting a question. It's best to give full disclosure on the first post so that the Community has all the information and have the whole picture to what's going on with your problem or problems. Otherwise it just a bandaid guess and a long drawn out process.

Note... Before doing the S n G make sure your car is fully warm... Your car is warm when a radiator fan comes on.

Andydana

Just completed the S n G. Oil looks great. And Is is at the appropriate level on the top "hot" dot. Drove it around and it is shifting fine. Now I guess I just wait and see what happens in the days to come?

Andydana

Sorry I should have taken more time for my first post to describe the whole problem

01acls

Cool, there are additional things you can check so don't be discourage yet. Good luck to you.

Andydana

Thanks 01 acls. I was getting prepared for the thought to have the trans rebuilt but I definitely don't want to got there if I don't need too.

Andydana

So the problem occurred again today. The car rev up but did not engage 3rd correctly it did roughly shift in after a few seconds. There was also noticeable rough shiftin in 1st and 2nd as well.

TheWrench116

iTrader: (1)

questions to answer.
1. what is the current mileage?
2. service record?
3. is the fluid level correct? are you sure your checking it correctly?? its a pain in the ass... :|

01acls

#11 2nd gear pressure switch
#6 Clutch pressure solenoid A/B
#8 Clutch pressure solenoid C
#18 O-rings



#17 Shift solenoid valve C (Right side)

01acls

Replace 2nd gear pressure switch and shift solenoid valve C.

#10 Harness plugs into Shift solenoid valve C. Ref Top pic. You will need to remove the cover plate for access to Shift solenoid valve C.


#18 O-rings, where there is a O-ring there is a small pipe. At the end of the small pipe there is a screen/filter. Check that for blockage. Replace all the O-rings and gaskets when doing your filter checks. It's important that the Pressure Control Solenoids A/B and C are fully seal so ATF fluild pressure does not get bleed off by leakage.


Ideally you should replace all of the noted Solenoids but the Pressure Solenoids A/B and C are not cheap. They're about $200ea.

Andydana

purchased at 115k now has 136k service was kept up not sure on all the details but the trans fluid must have been changed at some point because the trans cooler leaked and there must have been mixing of fluids. Think that work was done at around 90k. Yes I believe the fluid level is correct, it is at the top "hot" dot after the car has be driven.

TheWrench116

iTrader: (1)

if fluids mixed i could see you having a hurt transmission. changing out the electronics wont do much if the clutches are shot. drop the pan and have a look at the contents just make sure you have the correct fluid to fill it back up. and gasket or hondabond.