Hard shifts and stuttering at highway speeds
#1
Hard shifts and stuttering at highway speeds
So I figured I'd post about this and update it as i make progress. I have searched and haven't found anyone that has had this exact problem yet with the 7at.
I just took a family trip to NC and on the drive back the car was acting pretty strange. We took interstate 81 and there are definitely some hills and it was pretty hot out. I started getting some really hard shifts when I would go to accelerate, every once in a while it would slam into gear. This would only happen in th higher gears, usually 60+ mph, 1-4 seems to shift fine, if we pulled off at a rest stop driving around town it was fine.
Another thing that was happening during the trip was when going up a hill the car would shake occasionally and kind of stutter. Almost like it wanted to shift or it was stalling. The RPMs stayed constant and didn't fluctuate at all when this would happen. No check engine lights or stored codes when I got home.
If I stopped and let the car cool down, it seemed to help. Manually shifting while going uphill seemed to help too.
I scheduled an appointment with the dealer to take a look, and its due for 60k service soon so I'll update once I know more. It's a 2011 X with 58k, maybe the heat, hills and trans fluid at the end of its service life are all contributing factors.
I just took a family trip to NC and on the drive back the car was acting pretty strange. We took interstate 81 and there are definitely some hills and it was pretty hot out. I started getting some really hard shifts when I would go to accelerate, every once in a while it would slam into gear. This would only happen in th higher gears, usually 60+ mph, 1-4 seems to shift fine, if we pulled off at a rest stop driving around town it was fine.
Another thing that was happening during the trip was when going up a hill the car would shake occasionally and kind of stutter. Almost like it wanted to shift or it was stalling. The RPMs stayed constant and didn't fluctuate at all when this would happen. No check engine lights or stored codes when I got home.
If I stopped and let the car cool down, it seemed to help. Manually shifting while going uphill seemed to help too.
I scheduled an appointment with the dealer to take a look, and its due for 60k service soon so I'll update once I know more. It's a 2011 X with 58k, maybe the heat, hills and trans fluid at the end of its service life are all contributing factors.
#4
So took it to the dealer Wednesday, 60k service performed on the drive train. They couldn't get it to reproduce the problem and the fluid looked fine to them. They said it looked like it should for the mileage with no metal apparent. Tough to trouble shot a problem if they cant get it to happen.
So tonight on my drive home, about 30 min into the drive it starts to act up again...No codes, no SES. So, i guess ill see how it goes, maybe i can get it into the dealer and actually show them, or if not, just hope the trans explodes while still under warranty.
So tonight on my drive home, about 30 min into the drive it starts to act up again...No codes, no SES. So, i guess ill see how it goes, maybe i can get it into the dealer and actually show them, or if not, just hope the trans explodes while still under warranty.
#5
Update!!!
So, this past weekend I started pulling some of my engine mods to see if any of them could be causing or exacerbating the issues. I really didn't want to take it back to the dealer without narrowing it down some more and making sure I eliminated all possibilities. My procrastination was due to my dread of pulling off the cats again. They were such a bitch to do the first time. Anyone who has done this themselves will understand.
Well, they actually came off pretty easy, i think all that anti-seize i used really really helped. Also the second time around there was a lot less trial and error. anyway, this is what i found...
Bad cat.
You can see how its all just falling apart in there. this was on the drivers side. Its funny bacause when i got it tuned this side was running a little lean. they suspected i had an exhaust leak on that side somewhere.
The passenger side, is nowhere near as bad, but you can tell that the material is starting to fail.
Once i get the oem gaskets in, ill be putting the stock casts back on, but wow. I hope this is the fix, i cant believe how bad that looks. But that is what i get for buying a used pair of HFC. Lesson learned.
Well, they actually came off pretty easy, i think all that anti-seize i used really really helped. Also the second time around there was a lot less trial and error. anyway, this is what i found...
Bad cat.
You can see how its all just falling apart in there. this was on the drivers side. Its funny bacause when i got it tuned this side was running a little lean. they suspected i had an exhaust leak on that side somewhere.
The passenger side, is nowhere near as bad, but you can tell that the material is starting to fail.
Once i get the oem gaskets in, ill be putting the stock casts back on, but wow. I hope this is the fix, i cant believe how bad that looks. But that is what i get for buying a used pair of HFC. Lesson learned.
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#8
Registered Member
iTrader: (13)
No wonder I was prompted to replie here , LOL I had them on the car for less than 3k miles. So 20k and they blew apart, I bought them new , I wonder what the warranty was from FI and Lance? Sorry man
#9
no worries, **** happens. I doubt there is any warranty since im not the original purchaser. im just gonna throw the stock cats back on, maybe once i get this all sorted out ill pick up some Z1 or berks. I wouldnt mind getting one with the extra support bracket.
#10
Registered Member
iTrader: (13)
I know just feel bad those frincken things were brand new. I installed them the like 6 weeks later decided to sell the car an took them off. I now have the Z1's very happy with them. Price was great under 400$
#13
Got home from work early and installed my stock cats. Took it for a spirited drive through the hills and drove into work today. No issues. Crossing my fingers, I can understand the stuttering being gone, but why the hard shifts before I don't know. I'll update after some miles.
#14
Administrator
iTrader: (8)
I was always under the impression that catalyst material only breaks down when you're running rich, allowing non-combusted gas to ignite inside the cats. Over time, the broken material becomes blockage, further exasperating the problem.
Yes? No? IDK... not an engineer. But 20K on a set of cats seems just wrong.
Yes? No? IDK... not an engineer. But 20K on a set of cats seems just wrong.
Last edited by Rochester; 09-03-2015 at 07:57 AM.
#15
I was always under the impression that catalyst material only breaks down when you're running rich, allowing non-combusted gas to ignite inside the cats. Over time, the broken material becomes blockage, further exasperating the problem.
Yes? No? IDK... not an engineer. But 20K on a set of cats seems just wrong.
Yes? No? IDK... not an engineer. But 20K on a set of cats seems just wrong.
I was running for about 9 months after initial install of the HFCs without a tune, but everything should have been running lean at that point. So I don't "think" that should have caused the issue, there are plenty of people who have done the same with no problems. I don't really know enough though to make a better guess.
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SuicidalG37SGuy
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09-10-2015 06:01 AM