Mr Banks - is my AFR ok??
14 September 2002, 10:19 AM
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John - and anyone else 
Fitted the Autometer with all wires soldered into the correct ECU wires. 21 signal 9 power and 30 earth I think...
I let the car warm for 10 mins or so and it seems to work fine. At idle it will sit at rich, then drop to lean. This happens repeatedly and as far as I know this is correct behaviour as the ECU runs in either closed or open (cant remember which)The Autometer explaination of idle control also suggests this is correct. You can actually hear the engine drop off and revs dip VERY slightly, as it goes lean. When revs pick up, it goes rich.
When I blip or hold the throttle it goes rich, and as soon as the foot comes off it goes v lean, I guess as there is very little going through the injectors relative to air flow.
Does this sound ok?
MB
Fitted the Autometer with all wires soldered into the correct ECU wires. 21 signal 9 power and 30 earth I think...
I let the car warm for 10 mins or so and it seems to work fine. At idle it will sit at rich, then drop to lean. This happens repeatedly and as far as I know this is correct behaviour as the ECU runs in either closed or open (cant remember which)The Autometer explaination of idle control also suggests this is correct. You can actually hear the engine drop off and revs dip VERY slightly, as it goes lean. When revs pick up, it goes rich.
When I blip or hold the throttle it goes rich, and as soon as the foot comes off it goes v lean, I guess as there is very little going through the injectors relative to air flow.
Does this sound ok?
MB
15 September 2002, 11:44 AM
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Ta John,
Been driving around quite a bit now and it does seem to be a bit erratic... I thought it would have been more stable, as occasionally it flies round going off the scale lean, then jumps back to rich. On WOT its quite into the rich so that seems fine.
Just part throttle thats iffy. Worth going to the battery earth?!
MB
Been driving around quite a bit now and it does seem to be a bit erratic... I thought it would have been more stable, as occasionally it flies round going off the scale lean, then jumps back to rich. On WOT its quite into the rich so that seems fine.
Just part throttle thats iffy. Worth going to the battery earth?!
MB
15 September 2002, 12:00 PM
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So how is it of any use, apart from looking nice, at part throttle? What should I be looking for?
I assume the ECU is constantly backing on / off the fuel but I was hoping for more meaningful info from it. WOT is fine, happy to see it rich as it should be...
Thanks John
I assume the ECU is constantly backing on / off the fuel but I was hoping for more meaningful info from it. WOT is fine, happy to see it rich as it should be...
Thanks John
15 September 2002, 08:56 PM
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Ok as it was a nice day I rewired it to the battery.
Sod all difference! (I remeber a lot of debate about the battery being better
)
When on part throttle it flies into rich then back to lean. I think I will use the peak when it goes to rich as my reference point for the ratio. ie the peak is where my meaningful info is.
MB
Sod all difference! (I remeber a lot of debate about the battery being better
)When on part throttle it flies into rich then back to lean. I think I will use the peak when it goes to rich as my reference point for the ratio. ie the peak is where my meaningful info is.
MB
16 September 2002, 08:13 AM
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The peak is useless too. The only use is:
1. to see the lambda sensor is working
2. to estimate roughly the mixture at WOT
...hence for in car display I only have 3 LEDs as a reality check to make sure the MAF and lambda are working OK.
1. to see the lambda sensor is working
2. to estimate roughly the mixture at WOT
...hence for in car display I only have 3 LEDs as a reality check to make sure the MAF and lambda are working OK.
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