Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

Weird, erratic lambda log

General Tuning Discussion

Forum Posts



Tech Articles

Discuss all things tuning in this section. News, products, problems and results. 

= Resolved threads



Can someone explain to me why my lambda log looks the way it does?

It has some weird lean spikes in it.



Attached Files

How about fuel pump - is it 100 percent in good working condition?

I suspect it may be a misfire, due to insufficient ignition or a wiring fault causing an injector to fail to open at times - the latter can be intermittent and hard to isolate if there's a break that's making intermittent loss of contact.

A lambda measures the oxygen content in the exhaust, and if there's a misfiring sparkplug, or injector, then it will allow un-used oxygen into the exhaust, which the lambda reads as a lean spike.

Thanks for the replies.

I should also mention that at WOT, everything looks fine. And at Idle, it starts the same but then normalizes.

I don't hear misfires and the car feels fine.



Well, if it's not misfire and WOT mode works fine there is only one thing that comes to my mind from my previous experience- i once delt with a car that had a wrong value put in one of the tune cells related to fuel correction- it was way too much among normal figures and was kinda difficult to notice so it took a while to find that it was felse figure causing the lean spike...

It could be closed loop mode, dithering with too much gain.

We usually reply within 12hrs (often sooner)

Need Help?

Need help choosing a course?

Experiencing website difficulties?

Or need to contact us for any other reason?