Crazy Lambda readings

[PaulB]

Guys,
Just got the Blazt system on my pc so i can keep an eye on stuff on my ECU. Ive got a little hesitation problem at low revs and light throttle, and from what ive read it could be the lambda sensor.

The thing is, with the car at idle, the O2 value flickers from 0 - 100. Could this mean that my lamda is goosed?

Check it out guys and let me know what you think.........

Lamba value top right

 

[PaulB]

anyone ?

 

[chrism]

It looks like its maybe a bad connection.Check the connection whilst keeping an eye on the pc.
If the lambda is goosed then it´ll probably either show too rich readings or too weak.It can also be a bit slow.Id check the connection first.
Hold on the lambda only comes into play when its above say 2000 revs if Im not mistaken.It should be going on closed loop at idle.Check the lambda at 3000 revs or so like they do at the MOT.You should have a reading of roughly 1,00.

 

[Fusion Ed]

That is what its supposed to do. If at idle its going 0-100-0-100 every second or so then its working fine.

Ed

 

[PaulB]

rightyo, thanks for that ed.

Just thought it seemed a bit odd, dunno whether to replace it when i do my turbo tho, coz its off and its been on there 15 years.

 

[Fusion Ed]

Thats just what narrow band sensors do. They are not linear. They usually fail by being not so responsive. If it seems to respond quickly then its probably fine.

 

[PaulB]

Ed,
It also does it when im driving along, whether it be cruising or accelaerating hard. Just flickers to and from 0 - 100.
Is that right ?

thanks

 

[Fusion Ed]

Not quite, when you drive along light load low ish rpm, (cruise condition) the lambda should be going 0-100-0-100 etc, when you apply power it should go rich, when you throttle off it should go lean. If you apply any high load/high rpm it will most probably just show rich.

Ed