Help! A/F Ratio Readings

[donKey]

I have an Apexi Auto Timer with A/F ratio readings on my FD. I am experiencing these AF readings:

Aircond OFF and Headlights OFF: 14.2-14.6
Aircond ON and Headlights OFF: 14.8
Aircond ON and Headlights ON: 15.0

Are these readings normal? Why does the AF Ratio shows a leaner FD when Aircond and headlights are switched ON. Can some sifu give some insights on this.

Some extra info and findings: I realise my volt reading is around 11.x when I switch the aircond ON and headlights ON (volt readings flash) and 12.7 to 13.1 when they are both OFF (volt readings DON'T flash). 11.x is low, cos it is flashing. Has this any effect on the fuel pump? I understand that fuel pump operates at 12V? Could this be the cause of fluctuating A/F readings as I don't have a volt regulator or am I getting everything wrong here? Sifus sifus please help :)


Thanks.

 

[Erix7]

i never experience this b4...
mine is running 12.2-12.4 when i accel , normal driving 14 to 16

idle is 20.0 ( which is the car engine is running but the car is stopping)

i never experience any aircond on o air cond off condition
it goes all the same either when i on o off...

maybe ur tuning??
anyway i m using RE Amemiya ECU

wat r u using??

 

[donKey]

You are running rather rich :) I am using Mine's ECU. What A/F meter are you using?

Has this to do with the fuel pump as noted on my initial posting?

i never experience this b4...
mine is running 12.2-12.4 when i accel , normal driving 14 to 16

idle is 20.0 ( which is the car engine is running but the car is stopping)

i never experience any aircond on o air cond off condition
it goes all the same either when i on o off...

maybe ur tuning??
anyway i m using RE Amemiya ECU

wat r u using??

 

[phat7]

there are couple of variable factors here.

1. the rx7 being "older" will have to a certain amount "copper loss" due to ageing wiring and also due to our local mechanics whom will tap any 12v constant on your wiring loom. if this is the case then wire a 12v constant from battery to fuel pump.
it'll look something like this

Battery 12V+-----30-40amp fuse holder---------------Relay---fuelpump.

If this does not work i reccomend spending the weekend checking the harness (its a pain in the butt, but well worth it) make sure you have a multimeter handy.

 

[RERider]

hmmm....I'm not sure how accurate the apexi are, unless u got a separate O2 sensor rather than read from the ECU. Have u run for a dyno test after u installed ur Mines?

 

[Battousai]

I have a wideband O2 meter for rent. RM25/15 mins.

016 605 6628
daryl

 

[donKey]

Do you think installing a volt stabilizer will do any good?

there are couple of variable factors here.

1. the rx7 being "older" will have to a certain amount "copper loss" due to ageing wiring and also due to our local mechanics whom will tap any 12v constant on your wiring loom. if this is the case then wire a 12v constant from battery to fuel pump.
it'll look something like this

Battery 12V+-----30-40amp fuse holder---------------Relay---fuelpump.

If this does not work i reccomend spending the weekend checking the harness (its a pain in the butt, but well worth it) make sure you have a multimeter handy.

 

[donKey]

Yo guys and girls (if there are any lady FD owners :P )

I installed a volt stabilizer today. Tested the car and it seems that my A/F ratio has gone back to normal (14.x region). The volt reading has been stabilised to around 12.x V with everything switched ON. Seems like the volt stabilizer has done it for me. Hope this information is useful for other FD owners facing similar problems. Thanks.

Especially for those chinese members celebrating CNY and non-chinese members alike, have a woof year ahead! :P

Later, donkey

I have an Apexi Auto Timer with A/F ratio readings on my FD. I am experiencing these AF readings:

Aircond OFF and Headlights OFF: 14.2-14.6
Aircond ON and Headlights OFF: 14.8
Aircond ON and Headlights ON: 15.0

Are these readings normal? Why does the AF Ratio shows a leaner FD when Aircond and headlights are switched ON. Can some sifu give some insights on this.

Some extra info and findings: I realise my volt reading is around 11.x when I switch the aircond ON and headlights ON (volt readings flash) and 12.7 to 13.1 when they are both OFF (volt readings DON'T flash). 11.x is low, cos it is flashing. Has this any effect on the fuel pump? I understand that fuel pump operates at 12V? Could this be the cause of fluctuating A/F readings as I don't have a volt regulator or am I getting everything wrong here? Sifus sifus please help :)


Thanks.

 

[jasonlel]

I found out that if your voltage is below 13v, this means that your alternator is not charging your batt efficiently. Best is to be between 13v-14v.

Yo guys and girls (if there are any lady FD owners :P )

I installed a volt stabilizer today. Tested the car and it seems that my A/F ratio has gone back to normal (14.x region). The volt reading has been stabilised to around 12.x V with everything switched ON. Seems like the volt stabilizer has done it for me. Hope this information is useful for other FD owners facing similar problems. Thanks.

Especially for those chinese members celebrating CNY and non-chinese members alike, have a woof year ahead! :P

Later, donkey

 

[Alchemis]

Aircond OFF and Headlights OFF: 14.2-14.6
Aircond ON and Headlights OFF: 14.8
Aircond ON and Headlights ON: 15.0

is not too rich.. mine is even richer.. when i accelerate... its about 10 ~ 11 range... imagine that....i'm running stock :P

 

[phat7]

what are you using to base your figures? if its the apexi unit dont bother as its crap and besides is your o2 sensor new? get it done on a wideband for more accurate readings.

 

[jasonlel]

Totally agree.

Wide band sensor is the way to go.... :p :p

what are you using to base your figures? if its the apexi unit dont bother as its crap and besides is your o2 sensor new? get it done on a wideband for more accurate readings.

 

[jasonlel]

donKey,

Take a look at my posting, perhaps it can help you solve your problem.

http://www.zerotohundred.com/newforums/showthread.php?t=69334

I have an Apexi Auto Timer with A/F ratio readings on my FD. I am experiencing these AF readings:

Aircond OFF and Headlights OFF: 14.2-14.6
Aircond ON and Headlights OFF: 14.8
Aircond ON and Headlights ON: 15.0

Are these readings normal? Why does the AF Ratio shows a leaner FD when Aircond and headlights are switched ON. Can some sifu give some insights on this.

Some extra info and findings: I realise my volt reading is around 11.x when I switch the aircond ON and headlights ON (volt readings flash) and 12.7 to 13.1 when they are both OFF (volt readings DON'T flash). 11.x is low, cos it is flashing. Has this any effect on the fuel pump? I understand that fuel pump operates at 12V? Could this be the cause of fluctuating A/F readings as I don't have a volt regulator or am I getting everything wrong here? Sifus sifus please help :)


Thanks.