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Discussion Starter #1
Had the trans replaced and after a few years the vehicle will not go into first automatically, I have to manual put into first as I get rolling I put the shifter to Drive and then it works. Any help out there?
 

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So it stays in neutral, which is the gear before D, unless you shift down to 1/2?

What about if you shift down to just 3 or 4 instead of going all the way to 1/2, does it go into drive?

Initially I think the shift linkage is misaligned. But perhaps not if 4 or 3 don't work.

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All gears shift manually. I'm thinking a solenoid or range pressure switch. Manually again is ok but automatically it will not go into first when starting off. The sometimes I can drive in stop and go no problem and other times when I start from stop it will not go into first unless I do it manually.
 

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The same hydraulic circuits that you manually select are used by the computer in D, and even much of the same logic. So it isn't likely solenoid.

There is no range pressure switches. There are a few individual hydraulic pressure switches that stage hydraulic pressure for gear changes.

There is also a range selector switch that doesn't do much of anything regarding actually shifting. It lights up the lights on the dash for the gear you are in, and prevents starting in gear.

Your second reply isn't saying that the car will be driving in D fine for a while, and then after coming to a stop, it won't take off again without shifting to 1, is it?

I still think it is a misaligned shift linkage. The Acura shift linkage is a ridiculously engineered affair.

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Your second reply isn't saying that the car will be driving in D fine for a while, and then after coming to a stop, it won't take off again without shifting to 1, is it? Yes that is what is happening.
 

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When this happens, and if you don't shift to 1st manually, does the engine race like it was in neutral? Or does it bog down but move a bit like it is trying to start in 3rd gear?

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Engine revs thats it from stop, but say I am approaching a stop sign at slow speed it revs and then if I let it drop to normal rpm sometimes it will kick in.
 

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Discussion Starter #8
Engine revs thats it from stop, but say I am approaching a stop sign at slow speed it revs and then if I let it drop to normal rpm sometimes it will kick in. It is not like I am in gear it just revs.
 

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You have checked that the ATF fluid is full, right?

That sounds like a valve body problem, maybe a solenoid. You have no trouble lights on your dash for the engine or VSA, and the "D" light on the shift indicator isn't flashing?

I'll look in my factory service manual later to see if it has a troubleshooting diagnosis for this.
 

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No lights no codes that I know of. I just changed the battery so any codes are gone. Nod light blinking. First thing I did was check the ATF.
 

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I should have asked earlier if the transmission fluid was deep red to orange brown, with no whitish milkshake tinge?

What you are describing is called flaring after a downshift to 1st. About the only things you can check are fluid level, and you could check the shift cable if you are a little mechanical. After that, it gets really technical and you have to have specialty equipment to proceed.

I hope your replacement transmission if it was a rebuild, has a warranty. Sounds like they might have done a bad or incomplete job. If it was a junkyard transmission, you may have lost the lottery.

You could test the stall speed in each gear. I'd have to look up the desired stall RPM for each gear to tell you. But you have to be careful, because doing that wrong can further damage your transmission. And even getting the results doesn't narrow it down to 1 cause, it gets it down to 2-5 causes that again need specialty test equipment.


If you haven't actually been moving the shifter left into 1 to make it shift, and you've just been moving the shifter down to the bottom which is 2, and forces the car to skip 1st for starting on ice - then I bet you have a defective 1st accumulator or 1st clutch. It could also possibly be a worn ATF pump and the reving of the engine lets it build pressure to engage 1st.

After reading most of the AT section of the service manual it could be something else too. The logic, sensors, and actuators on these things are fantastically complicated. But even Honda thinks it is one of the items below based on their troubleshooting guide.

115188
 

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Discussion Starter #12
Thanks so much for your help. I'll let you know how it turns out so the next poor soul that has this happen will know what to do.
 
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