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Car hesitates when upshifting for 1st

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Old Aug 3, 2009 | 01:39 PM
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Car hesitates when upshifting for 1st

Has this happened to anyone else? Within the last two months or so under hard acceleration (65-70% throtle) the car pauses for about 2secs or so before upshifting from first. Its almost like shifting with stick. The engine rev's almost to red line then there's a noticeable monent before the tranny upshifts. This has happened once in DS mode and twice in D. This is a 08 with about 10k on it. I already know that when I take it to the dealer they'll ask for proof which of course I won't be able to provide.
Any suggestions or feedback is greatly appreciated.
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Old Aug 4, 2009 | 08:32 PM
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Anyone? Anything at all?
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Old Aug 5, 2009 | 06:33 PM
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sorry cant really say ive heard of this or seen it in either my old 5at or new 7at. sounds early but maybe a transmission flush will help the issue.
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Old Aug 5, 2009 | 06:44 PM
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Intermittent transmission shift issues are usually hard to diagnose.

Did you notice this shifting issue when the car is cold or after yo have driven for a while? Did it happen after a highway cruise or during local driving? Perhaps it was just after you beat on it a little bit? Depending upon the driving conditions, it may a simple adjustment or a more serious issue but with only 10k miles on the car it is likely minor.

Did you check the tranny fluid level level?
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Old Aug 5, 2009 | 08:54 PM
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I haven't checked the tranny fluids as the car was at the dealer about two months ago for an oil change etc. I've thought back about what/where it happened and in each case I was going up minor inclines - once going to the NJ turnpike, just after the last light. Once going up the incline for a bridge and the other time most recently going up an incline while going up an incline.

Its like the car is confused where I'm asking for more gas but it wants to upshift then just freeze's. Not sure if it should hold first or upshift. The pause is so distinct that in each instance I thought that I had knocked the car out of gear. I have on occasion accidentally knocked the car into neutral while driving causing the engine to rev with loss of forward motion. This is exactly how it feels.
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Old Aug 5, 2009 | 10:19 PM
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I've never experienced that in either my G37 or my G35. I have never seen it in any of the loaners either. Does it happen at full throttle as well?
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Old Aug 5, 2009 | 10:53 PM
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From: Northern NJ
Originally Posted by blackfunk
I haven't checked the tranny fluids as the car was at the dealer about two months ago for an oil change etc. I've thought back about what/where it happened and in each case I was going up minor inclines - once going to the NJ turnpike, just after the last light. Once going up the incline for a bridge and the other time most recently going up an incline while going up an incline.

Its like the car is confused where I'm asking for more gas but it wants to upshift then just freeze's. Not sure if it should hold first or upshift. The pause is so distinct that in each instance I thought that I had knocked the car out of gear. I have on occasion accidentally knocked the car into neutral while driving causing the engine to rev with loss of forward motion. This is exactly how it feels.
My diagnosis - Low fluid. As you go up these inclines in a low gear, the trans fluid is moved to the rear of the unit causing the shift delay due to hydraulic starvation. Check the fluid on a level surface - i suspect you are SLIGHTLY low. Just a few ounces will make a difference.
Good luck
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Old Aug 6, 2009 | 09:24 AM
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Originally Posted by bschurr
My diagnosis - Low fluid. As you go up these inclines in a low gear, the trans fluid is moved to the rear of the unit causing the shift delay due to hydraulic starvation. Check the fluid on a level surface - i suspect you are SLIGHTLY low. Just a few ounces will make a difference.
Good luck
Well I just checked the fluid levels and it is low. Hopefully this solves the issues. I have a set a service appointment for tomorrow so I'll update this post then.
Honestly it never dawned on me that I needed to check the fluids as I am on the most aggressive service plan from Infiniti and I didn't think that the fluids would drop off between service appointments. I also noticed that my oil level was a bit on the low side as well. Guess I should be more dilligent at checking these things myself and not depend on the dealer.

Thx to all that responded.
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Old Aug 6, 2009 | 10:00 AM
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my car has been doing the same sh*t.... taking it in tomorrow
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Old Aug 7, 2009 | 11:45 AM
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I thought this was a characteristic of the transmission. Mines has been doing this since the day I bought it only in Manual mode. The older BMW M3 with the SMG tranny has this same characteristic. Its like the tranny disengages from 1st to 2nd gear like a manual clutch. There is alse a hard down shift from 2nd back to 1st as well.
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Old Aug 7, 2009 | 12:38 PM
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i just had my shifter replaced. I have an auto, IO would never tought it would go bad.
car only has 20K.
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Old Aug 7, 2009 | 02:49 PM
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Originally Posted by RISKY GUY
i just had my shifter replaced. I have an auto, IO would never tought it would go bad.
car only has 20K.
What do you mean by shifter? The ****, or the tranny?
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Old Aug 9, 2009 | 08:52 AM
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Well I got it back yesterday and unfortunately they couldn't find the issue (no suprise there). However the master tech suggested that I (we) call HQ and file a complaint so that engineering can start investigating wether there is a more widespread issue.
Even though I didn't get that resolved the crazy squeaking/rattling from the sunroof/headliner/A pilar is now resolved.
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