Need some help tuning @ idle...makeshift logs within
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From: Port Tobacco, MD
Need some help tuning @ idle...makeshift logs within I finally pulled my spark plugs to get the car tuned and here's what we got:
Startup
Map: ~19.5 - - -~19.5
IAT: 63 - - - - - 64
Coolant: 115 - - 180
A/F: (14.0-14.5) - (15.5-16.0)
Timing (19-20) - (19 - 20)
Rpm: 950 - - - - 950
It looks like as the car warms up the fuel gets leaner. How do I lean it out slightly?
Phil
Startup
Map: ~19.5 - - -~19.5
IAT: 63 - - - - - 64
Coolant: 115 - - 180
A/F: (14.0-14.5) - (15.5-16.0)
Timing (19-20) - (19 - 20)
Rpm: 950 - - - - 950
It looks like as the car warms up the fuel gets leaner. How do I lean it out slightly?
Phil
The Fuel Air Multiplier table under the fuel tab controls target mixture based on coolant temp. I've read the method is to tune the VE tables in the idle ranges (400/800/1200) for the right hot mixture, then adjust the FAM table to richen things up when cold (and still in open loop).
I recently worked on a car with big cam and cold idle
problems, I brought down the Open Loop Fuel Air table
quite a bit in the "cool start" ECT area where high idle MAP
appeared to point.
What units is that MAP value? Way too high to be PSI (NA)
and way lower than my car's kPa, stock cam. Though maybe
at 950RPM I would have a lower MAP too.
You need to lean out both VE tables, keep them in sync.
I ended up leaning out all the way up into the 2000s as
logging showed the bottom end very over-rich.
At 115F ECT you should already be in closed loop and at
proper mixture. If you are rich at that point I would
suspect bad trimming, from the long tubes. Maybe you
could swap your old rear sensors to the front.
problems, I brought down the Open Loop Fuel Air table
quite a bit in the "cool start" ECT area where high idle MAP
appeared to point.
What units is that MAP value? Way too high to be PSI (NA)
and way lower than my car's kPa, stock cam. Though maybe
at 950RPM I would have a lower MAP too.
You need to lean out both VE tables, keep them in sync.
I ended up leaning out all the way up into the 2000s as
logging showed the bottom end very over-rich.
At 115F ECT you should already be in closed loop and at
proper mixture. If you are rich at that point I would
suspect bad trimming, from the long tubes. Maybe you
could swap your old rear sensors to the front.
