afr gauge help

[rb evo]

hi just fitted a afr gauge and on tickover goes right over to 18and then dont read a number but wen i rev it goes down is there a prob somewhere with the car and what afr should it be on tickover gauge is a aem afr and lambda is fitted in the decat pipe any help apreciated thanks

 

[RsvRob]

Wide band I presume??

Possibly an exhaust leak and it's drawing in air.
Is it fine on wot and cruising?

How do you not know what it should be on idle if you've fitted one??

 

[Tom2741]

Mine idles at around 15 with exact same set up as you. I've been having fuelling problems recently tho so prob not a good example to go off.

If you rev to say 2500 what does it go to then?

 

[rb evo]

ill check what it goes to wen rev but it does go down so prob a leak on exhaust ill try and see what happens when i drive it but ticks over perfect if that makes a difference cheers for help

 

[Tom2741]

Yeah, best off taking proper readings when the gasses are moving properly.

Check for leaks too though.

 

[rb evo]

i will see wen driving my friend has a smoke machine to test for leaks maybe worth trying that aswell cheers

 

[Simon@NTS]

Vehicles spec?

 

[B6lee]

Mine used to be on 18 at idle but only when stone cold. Then it would settle around 13-15

 

[rb evo]

It's a fq340 just fitted decat and down pipe and a hks filter and I will see what it's like after a drive and fully warmed up cheers