Vauxhall Workshop Service and Repair Manuals

Test	TECH 1	Notes	Nominal Values	Possible
Step	Display			Trouble
No.				Codes
* 06	IDLE CO POT.	Ignition ON	In general, the value
		Engine at idle speed	is between 0.9 and	65, 66
		(only active when idle	1.4 V for a required
		contact is closed)	CO content of 0.7 to
			1.2 Vol. % CO
			The permissible adjustment
			range is between
			0.3 and 4.7 V

 

 

Note:

 

The IDLE CO POT. has a permissible adjustment range of 0.25 to 4.81 V.

If the value lies outside this range, a trouble code will be set.

 

Using the IDLE CO POT., the injection time can be directly influenced over the whole load range.

If there are deviations, observe the O2 INTEGRATOR as well.

Turning potentiometer towards right (increased voltage) means an increase of the injection time (CO % increases).

A turn to the left means a reduction in the injection time (CO % decreases).

 

Example:

Adjustment to 0.1 V: injection time is increased by 0.25 ms

Adjustment to 4.0 V: injection time is decreased by 0.25 ms

 

There is therefore a total adjustment in injection time of max. 0.5 ms.

 

 

* only for 20 XE/20 XEJ engines

 

 

Trouble-shooting:                            Nominal Value:                            Cause of Fault:

(If nominal value is not attained)

 

The relevant terminal designations are under the mass air flow sensor plug insulation.

 

If the nominal values are attained -----> IDLE CO POT. in mass air flow sensor defective

 

Checking the IDLE CO POT.:

Ignition OFF

· With multimeter between Ter. 2 and                                                                             · Potentiometer defective

Ter. 6 (IDLE CO POT. signal lead):

Potentiometer at left stop:                                 0 to      30     Ohm

Potentiometer at right stop:                            900 to 1100      Ohm

 

Important:

 

With closed loop systems, ensure that the idle CO potentiometer is on a medial value of 1.4 V.

If a deviation is present which cannot be regulated by the oxygen sensor, this may be indicated by incorrect mixture integrator values or by storage of trouble codes 44 and 45.