What should my afr reading be on tickover? I ran the engine for a while last weekend and it was creeping up and up until it reached about 16 so I turned engine off!
Should this happen when car gets warmer but still stationary? Or should it remain constant? What sort of figures should I be looking for on tick over, accelleraiom and full throttle

[Edited on 26/8/11 by daniel mason]

Mine sits at 14.7 at idle, I've only had it ticking over for 10 mins or so but it didn't move much at all.
Edit to say at WOT (turbo) it drops to 12 ish.

[Edited on 26-8-11 by flibble]

Should have a steady idle somewhere between 13.5 and 15 IMHO. If you have no cold air intake it could be heating up and breathing warm air which is less dense therefore it takes in more air for the same fuel quantity and goes lean. Or another thing could be an air leak when its warmed up.
It wont get much higher than 16.5 then it will stall i'd think

Are you running open loop (no oxygen sensor)? If so it sounds like your temperature enrichment calibration is miles out - the mixture should normal be richened when the engine is cold and the enrichment should gradually be backed off as the engine warms.

Reading creeping up but going lean
16 is lean 12 is rich

I checked mine the other day [Zetec on carbs]

It doesn't seem to like running at tickover at anything richer than 14, and will happily run at 17-18.

It's about 15 now.

Stu

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.88 /.9 is how it should be or an AF of 13.25

15 /16 sound very lean and dangerous.