2001 Infiniti QX4 Harsh Acceleration Shift

NISSAN 240SX
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RYANKINGS
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2001 Infiniti QX4, 3.3L V6

Problem: when first accelerating the vehicle gears 1 and 2 do not respond correctly, there is an attempt to switch gears and pause and then a very abrupt change. With a bit of a rev in the engine during the pause.

After a few minutes, the changes become smooth and normal. The check engine light is on which seems to come on about everyday, whether something is wrong or not. When the light is off the problem persists.

Any ideas?

Ry
Apr 12, 2007 at 5:07 AM
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RASMATAZ
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What is this an auto or manual transmission
Apr 12, 2007 at 10:55 PM
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RYANKINGS
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Auto transmission
Apr 13, 2007 at 12:40 AM
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RASMATAZ
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[quote:ff0c4da5c1="ryankings"]Auto transmission[/quote:ff0c4da5c1]

Have the coolant temperature,throttle position,and vehicle speed sensors check. The computer takes these signals puts it all together and activates the shifting solenoids for the up and down shifts.

Now the question-when was the last fluid and filter changed.

Good Luck!
Apr 13, 2007 at 1:43 AM
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RYANKINGS
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It is at about 8000 kms (semi-synth) on the oil and needs to be changed, but this is not a new problem, it just seems to have gotten worse lately, it has always had a bit of this problem since i purchased it at 80,000 kms, it now has 220,000.
It is going in on monday to the mechanic.
Apr 13, 2007 at 3:41 AM
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RYANKINGS
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Thanks for your help
!!!!!!!!!!!!!!!!!!!!!!!!!
Apr 14, 2007 at 1:57 AM

Suggested Repair

Check the coolant temperature, throttle position, and vehicle speed sensors, which the computer uses to control the shift solenoids. Also check when the transmission fluid and filter were last changed and service them if due.

Conversation Summary

The owner of a 2001 Infiniti QX4 with an automatic transmission reports harsh, delayed 1-2 shifts with a brief engine rev when first accelerating; shifting becomes normal after a few minutes. The check engine light comes on most days but the problem continues even when it is off. The issue has been present since purchase and has worsened. An expert advised checking the coolant temperature, throttle position, and vehicle speed sensors and asked about the last transmission fluid and filter service. The owner said the oil needs changing and the vehicle is scheduled for a mechanic.

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