Helikido

Hi all,

I recently purchased a 2008 TL Base w/ Navi. It had about 91.5k miles on it when purchased. As I read through the forums for maintenance items to consider, I saw the DIY about the 2nd, 3rd, and 4th gear pressure switch for the 07-08 model with the RL-like tranny. Bought the three pressure switches from OEM Acura (linked in mentioned thread) and was planning on doing them sometime this week.

But, issues started to emerge:

• There is a delay in shifting going from park to drive when the car is warmed up. Doesn't happen when cold. The first shift is the 3rd gear shift, which happens smoothly immediately after shifting to D. Then 1.5 seconds later, the 1st gear shift happens, and it engages hard. Based on threads that I've read, this is due to the 3rd pressure switch going bad. Again, it only happens when the transmission is warmed up and it's not a cold start (or cool start after a small drive). I also think the ATF may have a part to play due to it being most sensitive to ATF temp. I checked it and it was pink. The lady we purchased it from had all recommended maintenance done at the dealership as well (verified via CarFax), and the pink color leads me to think it was replaced.

• P0796 & P0767 pressure control solenoid C stuck off / shift solenoid D stuck on codes where thrown just yesterday. My theory is: Those two codes are for the C & D solenoids and I doubt those two went out at the same instant. I think they where thrown due to bad pressure switches causing shift delays. I'm a transmission novice, but my understanding is that when the transmission wants to shift, it tells the solenoid of that gear to close, and then the shift happens after the pressure switch senses that enough pressure built up and the shift can now occur. If the pressure switch is bad (not in the sense of being stuck on/off, but rather having erroneous readings), the transmission will think that the solenoid is broken because it took too long to shift, since there's a considerable delay before the faulty pressure switch reads enough pressure is now built up.

• Transmission fluid level is at the lowest dot on the dipstick. I think this normal? It was checked when the car was warmed up. I will be doing a drain & fill at the dealership after the replacing the pressure switches.

​​​​The pressure switches will be replaced Weds or Thurs of this week. But if there's any insight that you guys can provide me with, that will be helpful! I did do some research about the codes I saw and I had no luck finding information relevant to the observations made in this case. Solenoids are very expensive compared to the pressure switches so I want to avoid switching them out if not necessary.

Thanks!

Helikido

Update: The codes cleared up by themselves today. So I think my theory may hold.

MATT2816

So have you noticed any significant difference in shifting after changing the pressure switches?

racerock

OP Is a 2 time poster... Help me, partial info and then nothing. Thread should be deleted, OP removed IMO.
Waste of time. Thanks for nothing.

zeta

iTrader: (1)

^

Chad05TL

Sounds like someone may have put the wrong transmission fluid in it for starters. I wonder where they took the car to have it serviced? If they took it to somewhere other than Honda/Acura dealer, then no telling what they put in the transmission. And if they did a complete Flush, that is also a No-No.

Without know what kind of fluid is in the car now, I would drain and fill the current system with 50% Redline D4 transmission fluid and 50% Honda DW1 fluid.
Each drain and refill takes 3 quarts. And you should repeat this process at least 3 times after you put at least 20 miles on the car after each time you drain. So dont do it just 3 times in a row immediately without driving it. You have to work the fluid around the transmission each time before you drain it again.

Also I do not think the pressure solenoids effects the transmissions ability to shift from park into R or D or back into Park. I think those shift solenoids are for only shifting. It is not a drive selector.
I think just the fluid is responsible for keeping a car from going into R or D from park.

Fluid Level: Fill it to the top dot. In fact, make sure the car and transmission is hot and then shut off the engine and immediately take a reading on the dip stick. If you see No fluid on the stick then Add 1/2 a quart and repeat the test. Or if the stick is just smeary and fluid is scattered on the stick and you can't tell where the fluid level is then add 1/2 a quart and repeat check.. I would Error on the side of Too full rather than Too empty. If it is too empty the transmission will burn hotter.. And you dont want it to get too hot. There is not even an oil cooler on these base TL transmissions. Only on the TypeS. So, dont underfill that transmission!. The book says to measure the dipstick within 30 seconds after the engine stops. But if you go up to 1 minute, the fluid will sink to the bottom of the pan and you will see a reading that is higher than what it is when the car is running. And that is not desired! You want to try to keep the fluid Up when the engine is Running and Hot. SO, if you read the dipstick when the transmission is cold and been off for a while, then I say the fluid level needs to be ABOVE the full line. You got it? I have my Fluid level sitting at the top mark when Hot and when I immediately turn it off. if I cannot read it,... Then I add some.. Like 1/2 a quart. And then start the engine.. then stop it.. then take another reading. The entire system reportedly holds 9 quarts. But 1 drain and refill is only 3 quarts. So, you have to do it several times to get out the existing fluid.. or at least begin to blend out the existing fluid.

The first drain and fill, you may be able to do 100% Redline D4. But after 1 or 2 drain and refill processes, I would go with with 50% Redline D4 and 50% Honda DW1 fluid.
I would fix that first then see how the transmission responds.
After your first drain and fill, GIVE IT SOME TIME TO READJUST. Start the engine, Then shift from P to D and then R and then P and then back and forth trying to get that fluid to circulate and hopefully you can get it to go into Drive so you can slowly drive it around the block until the transmission relearns.. So dont give up on immediately.. Just keep messing with the gear selector.. , Then go drive it if you can. Put 20 miles or a few days of driving (100 miles) and then do another drain and fill.. with 50/50 Redline and Honda fluid. But make sure it is At the Top mark when it is HOT.

I would do all that before moving on the the switches and solenoids.