[amitverma]

Can anyone here please elaborate what kind of calibration is done on the Lambda? I recently got mine tuned and the mechs at the CNG-fitting dealer totally played their cards to the chest. I didnt get a look at the various settings on the display. FYI, mine is a Tomassetto Achille kit.
I just wanted the info as the mechs only do a hit-trial job and maybe someone else can do a much better job at the calibration?

[HimuraKenshin]

Originally Posted by amitverma

Can anyone here please elaborate what kind of calibration is done on the Lambda? I recently got mine tuned and the mechs at the CNG-fitting dealer totally played their cards to the chest. I didnt get a look at the various settings on the display. FYI, mine is a Tomassetto Achille kit.
I just wanted the info as the mechs only do a hit-trial job and maybe someone else can do a much better job at the calibration?

As far as i know,
there are 3 LEDs on the Lambda control module, red, green and yellow
If the led is glowing red, it mean that the air-fuel misture is rich
green: Too lean
yellow: good air:fuel ratio

but if anyone can elaborate it would be great

[T1000]

Originally Posted by HimuraKenshin

As far as i know,
there are 3 LEDs on the Lambda control module, red, green and yellow
If the led is glowing red, it mean that the air-fuel misture is rich
green: Too lean
yellow: good air:fuel ratio

but if anyone can elaborate it would be great

Just want to share my experience, someone pls correct me if im wrong.

I was told that if all 3 lights glows alternatively then its considered a good setting.

Alternatively, another reliable way to set the cng idling is using a multimeter.

1. Connect the +ve probe to O2 sensor and -ve probe to battery ground.
2. Run the engine in petrol, let it come to operating temperature.
3. Note down the voltage reading in the multimeter when the engine is idling.
4. Switch to CNG and adjust the air/fuel mixture till you get the same voltage reading in the multimeter.

This will give you more accurate setting.

[WanderNomad]

The lambda I have on my car can be connected to a laptop. Obviously I had to pay more for this.

[T1000]

Originally Posted by WanderNomad

The lambda I have on my car can be connected to a laptop. Obviously I had to pay more for this.

WanderNomad, you must be using a sequential kit. It doesnt use the cars ECU, it uses a separate "CNG ECU "

[WanderNomad]

Of course not! Its not a sequential kit.

[T1000]

Originally Posted by WanderNomad

Of course not! Its not a sequential kit.

Ok, im not sure... because during my kit installation, i saw the mechanic connecting a laptop to a optra to tune the cng kit .. i was like im also paying money, so asked him to connect the laptop to my car as well and tune it.

the guy was laughing and said it can be used only in seq kit. :-))

[rdkarthik]

Not specific to your kit, most kits use stock gasoline injector duration as a reference for CNG injector duration. Since the air-fuel ratio is controlled by the stock ECU with feedback in place, the CNG injector air-fuel ratios should be closely matched (to original ratios at the time of switchover and subsequent adaptation) to stay within tolerance of original ECU control to prevent check-engine lights, etc.