Tickover adjustment

[Dave connors]

what is the correct method for adjusting the tick over on a sigma engine is it done by adjusting the throttle cable or the screw on the TB

[oilyhands]

Idle should be controlled by the ECU. But.. there should always be slack in the cable, so I'd say via the throttle stop.

Oily

[ChrisC]

Is your Sigma a 150? 

The idle speed is controlled by the ECU, but the throttle does need to be open enough to maintain that engine speed, which is a mechanical adjustment. 

 

[Tom_Arundel]

Why do you need to adjust it?

[ChrisC]

My experience is with a fair few Sigmas 150s mine and others, and one 125.  The 125 once set seemed to say set, but my 150 liked a tweak about once a year. 

 

[Dave connors]

mine is an ex sigmax car it does run very rich and struggles to tick over the emissions would not get though an mot at the moment not sure if the lamda sensor is shot which wouldn't help gues it needs to go on a rolling road and get tuned

[Tom_Arundel]

Unplug the sensor and see if it makes a difference.

[ChrisC]

Sounds classic lambda sensor to me.  But agree with Tom, unplug it and test.  It won't pass an MOT without it, and it will still be rich, but it won't be at the extreme of the possible adjustment.

If it is faulty, try to stick with quality Original or OEM replacements (Ford or Bosch) and avoid fakes.  

[Dave connors]

Makes no difference when its unplugged so it looks like a new lambda sensor

[Dave connors]

Does anyone know the part number of the lambda sensor I've taken a look at mine and the numbers are vary faint and nothing shows on an Internet search on the numbers I can see

[Jonathan Kay]

Private Message sent.

[Iain McCallum]

Hi Dave,

Mine was replaced a bit ago on my Sigma 150. It is a Danfoss MBS 1350 (063G1333)

Cheers Iain