O2sensor code came up replaced all 4 runs fine.

Tiny
ANONYMOUS
  • 1997 NISSAN PATHFINDER
  • 143,000 MILES

O2sensor code came up replaced all 4 runs fine when cold then starts jerking and bucking idle goes up and down only car I have need help

Thursday, November 22nd, 2012 AT 2:41 PM

7 Replies

Tiny
KHLOW2008
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What were the trouble codes? Are the codes still present after replacement of O2 sensors?
Did you check the spark plugs and related components?

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Thursday, November 22nd, 2012 AT 2:53 PM
Tiny
DEBBIESHAFFER-HEATHERMAN
  • MEMBER

All o2 sensors were cleared
checked plugs and wires they were fine

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Thursday, November 22nd, 2012 AT 5:15 PM
Tiny
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Do you have coolant losses issues or overheating issues?
What is the idling speed at operating temperature?
Try cleaning the throttle body and IAC and see if the idling stabilises.

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Thursday, November 22nd, 2012 AT 5:57 PM
Tiny
DEBBIESHAFFER-HEATHERMAN
  • MEMBER

No loss of coolant and no overheating issues
Idling speed 75-80 thousand rpms
What is an IAC?

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Thursday, November 22nd, 2012 AT 6:00 PM
Tiny
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Idle Air Control Valve. Idling speed is correct. So shouldn't be a fult with the idle control.

Misfiring should be the cause and were the spark plug wires ohmed out? Have the injectors checked and if possible, use a scan tooll to monitor the Throttle Position Sensor, MAF and injectors.

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Thursday, November 22nd, 2012 AT 6:50 PM
Tiny
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Rpm gauge goes up and down when vehicle warms up

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Friday, November 23rd, 2012 AT 1:23 PM
Tiny
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Maybe the IAC is not responding as required. Try cleaning it.

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Friday, November 23rd, 2012 AT 1:27 PM

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