CX9 GT Problem, hesitation while driving

J

johnnyjames

Member
:
2007 mazda cx-9
While driving my wifes 07 car with approx 130k miles, it appears that when youre driving around 45-60mph and you apply the petal for more fuel, the car thuds,ker-chunck, not sure how to explain it, it doesnt happen while the car is shifting or down shifting, just seems to "cut out "or "stall" for a sec, there are no engine lights on the car, does not seem to do it on low speeds that we can tell as of yet, thinking it may have something to do with the TPS or throttle, as well I would also like to know if these cx-9s have a fuel filter as I am sure that would be a good idea to change at this point, Ive tried to locate one at like the discount stores and they never seem to have one or cant tell me if there is even one. Where is the TPS can it be cleaned or any part of the TB be cleaned.
Thanks JJ
BTW the Transmission fluids is fine
 
Welcome to the forum. Yes, it could be many things. Fuel filter, fuel pump, injector, bad coil(s), throttle body, bad gas, trans issue, also could be the transmission overheat issue which Mazda has a tsb for. (mazda also has technical service bulletins for bad coils, throttle body, and ecm reprogram). Sounds like you may need to take it in. Not sure where the fuel filter is located...try crawling under the car and follow the fuel line and see if you can find it under the car.
 
If I have to entertain a guess, it sounds like the torque converter refusing to let go.
TC is part of the transmission. At 130K miles, have you ever changed the transmission fluid?
If not, it might be the 1st thing to try to see if that improves it.
 
Have had the tranny flushed with not any change

ceric said:
If I have to entertain a guess, it sounds like the torque converter refusing to let go.
TC is part of the transmission. At 130K miles, have you ever changed the transmission fluid?
If not, it might be the 1st thing to try to see if that improves it.
Click to expand...



We have had the tranny flushed around 80k miles by the dealer and again here at 130k mile, which did not seem to make any change, also wife noticed that is seems to be between 45-60 mph and if you are driving along on any type of incline either it be a mild hill or steep hill, maybe more so on a mild hill.

Thanks
 
I would add a can of Sea Foam injector cleaner to the fuel before I did anything. Directions on the can. Mine hesitates a little when I punch it, but I understand that to be normal - and surely not what you are describing.
 
Here is why I guessed what I guessed (i.e. TC).
Above 42mph, CX9's transmission shifts to 6th gear. (it happened betwen 45-60mph)
At 6th gear, the TC is almost always engaged to save fuel.
When you press gas pedal while it is at 6th, the TC needs to disengage first, and down shift to 5th or lower.

If ATF overheats, there is a light and transmission enters a limp mode.
Other issues mentioned above could happen in any gears or speeds, in my opinion.
 
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Anyone have any ideas on this, I have the exact same problem. Not sure I buy the spark plug issue, it's only when going up hill and with slight acceleration of pedal while in 6th gear.
 
sfollenius said:
What about this, two folks have a similar problem and ended being some sort of single misfire due to spark plugs. I have the same issue and will change mine to see if it fixes!

http://www.mazdas247.com/forum/showthread.php?123709704-gear-shifts-at-6th-gear
Click to expand...

I'm going to guess that this is what it is. I have a 2010 9 & also a 2008 Ford Taurus X - same v6 Duratech Engine but 3.5 rather than the Mazda 3.7. At around 120K in the Ford, it started just what you're describing - hesitating/clunking when accelerating lightly or up a slight incline that does not require a downshift. Changed the plugs and the problem went away. I thought it was the transmission as I had recently had some problems repaired on that but when I called my transmission shop, the guy thought it may be the plugs - doesn't make sense because the car runs smooth otherwise.

Try the plugs and I'm pretty sure you'll be golden.
 
Shouldn't the plugs be replaced at 100k?
I thought that is on the maintenance schedule.
 
I'm having a similar problem. It's a 2009 CX-9 Touring model with about 90k miles on it. When cruising in 6th gear and at low speed (about 45-60 as mentioned) and you press the pedal, it sometimes has a thunk-clunk that will occur. It's almost like it can't decide what it wants to do. It doesn't happen when using the manual mode or the other gears. Just low speed in the high gears. Trans was flushed at about 68k from the previous owner. I'm thinking of calling the dealer unless someone has something else I could try. I appreciate your thoughts.
 
TK421 said:
I'm having a similar problem. It's a 2009 CX-9 Touring model with about 90k miles on it. When cruising in 6th gear and at low speed (about 45-60 as mentioned) and you press the pedal, it sometimes has a thunk-clunk that will occur. It's almost like it can't decide what it wants to do. It doesn't happen when using the manual mode or the other gears. Just low speed in the high gears. Trans was flushed at about 68k from the previous owner. I'm thinking of calling the dealer unless someone has something else I could try. I appreciate your thoughts.
Click to expand...

Read my issue in the following thread and see if this is what you are experiencing

http://www.mazdas247.com/forum/show...iler-hitching-quot-sensation-in-Drive-6/page2

I had ignition coil defective. Some other members had spark plug causing this issue.
 
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Well, my wife took it to the dealer today and, of course, when they drove it nothing happened. They looked at the trans fluid and said it looked "fine." My wife did say yesterday, though, that it had been happening pretty much constantly. Makes me lean more toward the coil issue. I'll go back to the dealer on Sat and go with a drive with a tech and see if I can get it to do it again.
 
Update: I took it by the dealer last weekend and got the service manager to ride with me and I got it to do it. He said it was most likely shift logic and he was going to check to see if there was an updated algorithm. A week went by and no call. So my wife took it in again for me and this time a tech rode with her and it didn't do it. Argh! We already know it does it and he said all they wanted to do was look at the program so why another test drive? This weekend I'm going to swing by again and see if I can get the tech, manager, and Santa all in the CX-9 for this so we can finally start on a fix! It's low speed (40-45 mph), fully warmed up, 6th gear, and slowly roll into the throttle. If you stab it, sometimes it'll do it then, too.
 
Update 2: Finally got the tech to ride with me and I was able to get it to "thunk". It's usually around 6th gear at 40-45 mph and a slow roll into the throttle. He said it's definitely not a misfire like he was thinking at first based on where you feel it. Not up front, more like in the middle. I do have an extended warranty by Mazda since it was a CPO vehicle, but here's the hitch. Mazda (not my dealer) says "I" cancelled the warranty back in the beginning of April. Well, I bought the car at the end of April, so I didn't do crap! I still have all my paperwork that proves that I bought and paid for the warranty and that the transfer case and "all lubricated parts" are covered. Looks like I might be in for a little bit of a fight with corporate.
 
Update 3: Transfer case removed and replaced by the dealer under the CPO warranty. Good to go now. :)
 
Update 4: Until it started thumping again. However, it definitely seemed like it was more forward and it was more infrequent. I decided to change the spark plugs and clean the TB while I was in there since that is what the dealer was going to do next (but not under warranty since the plugs are not covered) and that was a tedious but not overly difficult job. I did myself a favor and after fighting those two clamps at the back of the engine bay I went and bought one of those hose clamp tools. Totally worth the $35! Got both off in about 10 seconds after fighting them for about 30 minutes.

I got the spark plugs removed and 2 of them were gapped at .055, one was at .060, two were at .072, and one was at .085! So that might have been causing some of my misfire issues since that is now what I think was the leftover problem. She's running good today and I'm a happy camper!
 
Why were the gaps on the plugs all over the place? Aren't they supposed to check the gap on each plug before putting in. I guess whoever did that part of the job wasn't in a good mood. What kind of hose clamp tool did you get? can you put a pic up. I guess i will have to change these plugs soon before that starts happening to me.
 
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