Petrol Diagnostics

Back to Forum

Post a Response

Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312 - Fixed #

Posted by Jon Flanagan on November 11, 2011, 6:26 am

Year of Manufacture *: 2006
Engine Size and Code *: CR12E
( Optional ) Scanner Used: Solus
( Optional) Fault Codes: P0132

Hi

Poor idling, flat spot on acceleration. Gas test OK but O2 at 5.00/6.00. Checked live date, both lambda sensors at 1.275 Volts

Possible throttle body?

Cheers Jon

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by Pete Mutlow on November 11, 2011, 7:33 am, in reply to "Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Message modified by board administrator November 11, 2011, 7:44 am

Evening Jon,

The fault code relates to a high voltage on the Lambda Sensor circuit which it is at 1.275v. This could be due to a poor earth or a faulty sensor. Does the Lambda Sensor switch or react to blipping the throttle? High 02 indicates a lean mixture which also could be due to an air leak. I would check these first before moving onto anything else.

Regards

Pete M

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by aidan birley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT2879' width='330' height='300' border=0 style='border:none;'> on November 11, 2011, 8:29 am, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Aidan Birley

Hi

Check actual sensor signal voltage on BOTH sensors ( with plug connected).

I think 1.2 is the highest voltage that ECU will report on live, I had one that was over 4 v when measured.

These had a problem with ECU wrongly reporting sensor 2 fault as a sensor 1 fault

You need to check + confirm condition of BOTH sensors next.

Cheers Aidan

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by Chris Angus <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5111' width='330' height='300' border=0 style='border:none;'> on November 11, 2011, 3:43 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"

I've read quite a lot about these but only seen it once myself. the heater curcuit shorts and causes a high voltage. fix is to replace both lambda sensors, but as Aidan said, check first.

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by kev adam <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat1645' width='330' height='300' border=0 style='border:none;'> on November 11, 2011, 8:06 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Kevin Adam

disconnect the rear lambda sensor and look to see if the front one starts reading normally.
done same fault in the past and it was the rear lamba causing fault
hth kev

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by Steve Kefford <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1094' width='330' height='300' border=0 style='border:none;'> on November 12, 2011, 8:05 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Stephen Kefford

Had a number of these now and it's always been no.2 sensor at fault, as already said, unplug it and see if no.1 comes in line.

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by martin simonsohn <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3223' width='330' height='300' border=0 style='border:none;'> on November 13, 2011, 2:38 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Martin Simonsohn

one silver bullet coming up
please check the ground on the O2 sensors
you will probably find bad earth retest earth at ecu it will be the same
have had 4 of these now all with ecu ground track faulty
what i have done to save the customer money is to wire another earth in and that has proved to be OK and all the customers have had no further problems
hth martin

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by Michael Whitworth <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5568' width='330' height='300' border=0 style='border:none;'> on November 13, 2011, 4:31 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Mike Whitworth - Administrator

Hi John,

>>>one silver bullet coming up<<<

I suspect your silver bullet is tarnished as the one already shot by previous posters is much shinier in my experience.

This problem is quite well known now and I have to admit the first time I experienced it I spliced in a separate earth independant of the ECU. But later I realised it was the rear sensor pulling the earth up sometimes as high as 5 or 6 volts!! Affecting both sensors. And as already stated the ECU can only report an output in live data of around 1.2v.

I would advise it better to eliminate the lambda sensor fault by testing as described earlier, then and only then would you look at the possibilty of an ECU internal earthing issue.

Regards,

Mike

M.O.M. Miserable Old Manc

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by martin simonsohn <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3223' width='330' height='300' border=0 style='border:none;'> on November 14, 2011, 5:06 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Martin Simonsohn

hi Michael Whitworth
when i tested the ground with a scope it gave a reading of 1v and the O2 sensor wasn't switching i must admit to not checking the rear sensor but having checked the ground all the way back to ecu on all 4 cars that i have dealt with i found the same symptom and the same repair has proved to be ok

could you explain how a ground can be "pulled up"
as surly a ground is a ground and should be less then .2v

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by Mark Carter <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on November 14, 2011, 9:10 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Mark Carter

Hi Martin,

>>> could you explain how a ground can be "pulled up"
as surly a ground is a ground and should be less then .2v <<<

Some earths are "pulled up" from true earth via resistors inside the ECU called pull up resistors. (Think of it as part of a voltage dividing circuit)

One of there common jobs is to provide a "Floating" earth to help the ECU with its EOBD monitoring role.

Regards Mark

PS. if you search "Floating earth" on this site you should find some good explanations.

Modern cars, Its all wizardry and witchcraft

Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312

Posted by martin simonsohn <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3223' width='330' height='300' border=0 style='border:none;'> on November 14, 2011, 10:12 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Martin Simonsohn

i understand floating grounds but the ground on the micra O2 sensor isnt a floater its just a ground so therefore if its pulled up there for its not got a good ground

Fixed #

Posted by Jon Flanagan on December 1, 2011, 9:33 pm, in reply to "Re: Nissan Micra CR12E 2006 - Flat spot on acceleration, code P0312"
Message modified by board administrator December 2, 2011, 1:57 pm

Thank for all your help lads. I tested lambda sensors after reading all your posts found fault with rear lambda sensor

(FIXED) Cheers Jon

« Back to index

[ Petrol Diagnostics ]

Copyright © uk autotalk