Transmission issues?

SC300ES

Member
On our 2008 AWD between 40-60 mph and gear indicator at 6, it feels like the transmission is hunting for the right gear where it shifts up and down. It kind of feels like the car is bucking but very slightly. Once we hit about 60 it disappears. My fluid levels are right, there is no burning smell and everything sounds and works below 40 and above 60.

Car has about 45k miles.

Any ideas?

Ed
 
I'm not sure if it's the same issue, but I had a 'fish bite' kind of feeling when traveling the same speed in 6th gear. Kind of a stuttering/jerking. I thought it was the transmission so I took it to the dealer. The first dealer couldn't figure it out. The 2nd dealer hooked up some diagnostic equipment and replicated the issue. It turned out that 2 of my ingition coils were bad. They've seen it before. It wasn't cheap to replace, but I changed all of them 'while they were in there.'
 
I'm also witnessing similar issues. 6th gear near 45mph and 5th gear at 35mph I notice it. Oddly tho switching to manual mode, the "hunting" disappears.

Edit: Just wanted to update this post. I replaced all 6 spark plugs and the back 3 ignition coils. The problems I mentioned have disappeared. My plugs have a gap of maybe .9 as opposed to the .55 the service manual suggests. Pretty bad.
 
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Glad all you guys got everything sorted out, quick question did any of you experience a "shutter" or slipping when the car shifted from 4th to 5th or sometimes 5th to 6th ? im having the same issue as you guys when in sixth it jumps around a little bit, but i also have a shutter at slow speeds in the previous mentioned gears and wanted to see if this is something i should look into before i look into a transmission replacement. THanks,
 
I'm not sure if it's the same issue, but I had a 'fish bite' kind of feeling when traveling the same speed in 6th gear. Kind of a stuttering/jerking. I thought it was the transmission so I took it to the dealer. The first dealer couldn't figure it out. The 2nd dealer hooked up some diagnostic equipment and replicated the issue. It turned out that 2 of my ingition coils were bad. They've seen it before. It wasn't cheap to replace, but I changed all of them 'while they were in there.'

correct, a stuttering feeling like this when the engine is under load at low RPM is usually an ignition coil issue. if you don't change your spark plugs regularly, your ignition coils will wear out at a faster pace.

in OP's case where he complained of gear hunting, that sounds like a shift solenoid issue. replace them.
 
Can anyone advise on how you can replace the ignition coils? Thank you

The engine is a "Coil on Plug" design so there are 6 ignition coils. They interface directly to the spark plugs. The 3 on the front side of the engine are very easy to get to, but the 3 on the back side are more of a challenge. There is a thread on here covering how to replace the spark plugs (https://www.mazdas247.com/forum/showthread.php?123773226-How-to-get-to-the-CX-9-spark-plugs). You can reference the instructions in there to get to the coils.
 
The engine is a "Coil on Plug" design so there are 6 ignition coils. They interface directly to the spark plugs. The 3 on the front side of the engine are very easy to get to, but the 3 on the back side are more of a challenge. There is a thread on here covering how to replace the spark plugs (https://www.mazdas247.com/forum/showthread.php?123773226-How-to-get-to-the-CX-9-spark-plugs). You can reference the instructions in there to get to the coils.

Thank you!
 
if you have determined that it is a transmission issue and not an ignition coil. change the transmission fluid/filter and replace all shift solenoids.
 
if you have determined that it is a transmission issue and not an ignition coil. change the transmission fluid/filter and replace all shift solenoids.

Thank you. Do you know if there is a way to test the ignition coils? I called the Mazda dealer for a price on the ignition coils and realized that they sell the ignition coils individually. In order to rule this out, I am guessing I would have to change all 6 of them.
 
Thank you. Do you know if there is a way to test the ignition coils? I called the Mazda dealer for a price on the ignition coils and realized that they sell the ignition coils individually. In order to rule this out, I am guessing I would have to change all 6 of them.

You can pull the coils and test the resistance with an ohmmeter. There is a thread on this forum that has the procedure. Otherwise, I think the test procedure is in the service manual, which can also be found on the forum somewhere. You should be able to find it with the search.
 
You can pull the coils and test the resistance with an ohmmeter. There is a thread on this forum that has the procedure. Otherwise, I think the test procedure is in the service manual, which can also be found on the forum somewhere. You should be able to find it with the search.

Thank you! I am reviewing service manual and will check the forum as well.
 
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