hi there i have just fitted an air fuel ratio meter,fitted it to pin 6 on the ecu on the 22 pin block as i found out through searching on the forum, seems to work ok,reads optimal but just above the lean when on tick over,what should these things read?i cant take out for a blast as it goes for mot next weekend so not road legal at the moment,it also has an adjustable fuel pressure regulator with gauge which reads 2.5-3 bar? i dont know what this should be set at ,my spec is: 95 wrx td05,front mount,full stainless 3" decat,z4 ecu and have a rolling road print out of 311 bhp/268torque(dont know what the boost is set at,1 bar i believe but cant say for sure) but a replacement engine has been fitted since then as i bought as a non runner due to bottom end failure.any help would be superb, thanks bryan

 

Really needs to be set up on a rr mate to know if it is running rich or lean and then adj accordingly but as a rough guide, like you say between 2.5/3. Last thing you want it for it to lean out and kill your engine mate. If it was on when you got the car and it was set at that already this could have been why the car was a non-runner !??! Better safe than sorry mate, get it done properly..

 

IIRC with the vacuum pipe removed you should see 3 bar fuel pressure at idle.

HTH

dunx

 

afr readings off the standard lambda are a very 'rough' idea and shouldn't really be used for tuning.

 

thanks for the replies guys,with the vac disconnected it reads 3 bar so that would be ok,i am a bit worried there wasnt enough fuel pressure on the last engine for the tuning it has,the afr meter was installed just as a rough look at what was happening.i will know more about how it runs next weekend after mot when im able to give it a bit load,just wondered how other members using afr's get on with the readings and on a lightly tuned engine like mine,what should the fuel pressure be set at, what boost would be needed on a td05 to give 311bhp? i would have thought it would be more than 1 bar but thats what i am told it was running. thanks again bryan