wideband reading at idle
12-16-2014, 09:43 AM
#1
TECH Enthusiast
Thread Starter
iTrader: (12)
Join Date: Aug 2007
Location: Rutland, MA
Posts: 590
Likes: 0
Received 0 Likes
on
0 Posts
wideband reading at idle My car has always done this and this is my first carb motor I have ever tuned with a wideband so maybe its normal. At first start up it reads way lean, 17-18. As it idles it slowly drops and settles to where I want it around 13. It does the same on deceleration, it stays where it should while driving and idling at a stop light it slowly comes down, sometimes dropping even lower. The longer it idles, the fatter it gets
Has anyone else noticed this? is it common to carbed motors? Its not a problem, the car runs great and I have it tuned perfectly, I have always noticed this since I put the wideband in.
Has anyone else noticed this? is it common to carbed motors? Its not a problem, the car runs great and I have it tuned perfectly, I have always noticed this since I put the wideband in.
Last edited by Horsepwraddict; 12-16-2014 at 10:01 AM.
12-17-2014, 09:41 AM
#2
My car has always done this and this is my first carb motor I have ever tuned with a wideband so maybe its normal. At first start up it reads way lean, 17-18. As it idles it slowly drops and settles to where I want it around 13. It does the same on deceleration, it stays where it should while driving and idling at a stop light it slowly comes down, sometimes dropping even lower. The longer it idles, the fatter it gets
Has anyone else noticed this? is it common to carbed motors? Its not a problem, the car runs great and I have it tuned perfectly, I have always noticed this since I put the wideband in.
Has anyone else noticed this? is it common to carbed motors? Its not a problem, the car runs great and I have it tuned perfectly, I have always noticed this since I put the wideband in.
W/a carb, it's gonna move around a bit. @ start up, it takes some time for the O2 sensor to warm up &/or fueling from carb to balance out. So, she's gonna show lean for a bit (normal). Am not sure why you want 13:1 @ idle, but it can be adjusted. How it's adjusted depends on the carb. Normally, idle A/F ratio is set to stoich which is 14.63:1.
12-17-2014, 03:34 PM
#3
It is typical for a carbureted car without a choke to be lean and a bit fussy at idle when it is cold. As the car warms up it will typically read richer on the wideband.
Once the car is warm, the idle should be fairly stable. I always tune my car for best warm idle. I know racers who tune their car to idle fat because they often cold start it and don't want to deal with it being fussy until it warms up.
Not all carbed cars will be willing to idle consistently at a 14.5:1 wideband reading. In fact, that is fairly uncommon for a car with a decent sized cam to maintain such a lean wideband reading at idle.
My car behaves best when the idle varies between 13.5:1 - 14.2:1.
Once the car is warm, the idle should be fairly stable. I always tune my car for best warm idle. I know racers who tune their car to idle fat because they often cold start it and don't want to deal with it being fussy until it warms up.
Not all carbed cars will be willing to idle consistently at a 14.5:1 wideband reading. In fact, that is fairly uncommon for a car with a decent sized cam to maintain such a lean wideband reading at idle.
My car behaves best when the idle varies between 13.5:1 - 14.2:1.
12-17-2014, 07:45 PM
#4
On The Tree
A/F readings can be off alot if the cam is big and large exhaust pipes. Also if the exhaust ends close to the O2 sensor it can read lean from backwash.
Aleck
Aleck
12-18-2014, 04:10 AM
#6
TECH Enthusiast
Thread Starter
iTrader: (12)
Join Date: Aug 2007
Location: Rutland, MA
Posts: 590
Likes: 0
Received 0 Likes
on
0 Posts
W/a carb, it's gonna move around a bit. @ start up, it takes some time for the O2 sensor to warm up &/or fueling from carb to balance out. So, she's gonna show lean for a bit (normal). Am not sure why you want 13:1 @ idle, but it can be adjusted. How it's adjusted depends on the carb. Normally, idle A/F ratio is set to stoich which is 14.63:1.
It is typical for a carbureted car without a choke to be lean and a bit fussy at idle when it is cold. As the car warms up it will typically read richer on the wideband.
Once the car is warm, the idle should be fairly stable. I always tune my car for best warm idle. I know racers who tune their car to idle fat because they often cold start it and don't want to deal with it being fussy until it warms up.
Not all carbed cars will be willing to idle consistently at a 14.5:1 wideband reading. In fact, that is fairly uncommon for a car with a decent sized cam to maintain such a lean wideband reading at idle.
My car behaves best when the idle varies between 13.5:1 - 14.2:1.
Once the car is warm, the idle should be fairly stable. I always tune my car for best warm idle. I know racers who tune their car to idle fat because they often cold start it and don't want to deal with it being fussy until it warms up.
Not all carbed cars will be willing to idle consistently at a 14.5:1 wideband reading. In fact, that is fairly uncommon for a car with a decent sized cam to maintain such a lean wideband reading at idle.
My car behaves best when the idle varies between 13.5:1 - 14.2:1.
I figured it was normal, It was always in the back of my head while tuning though. I guess I just needed reassurance.
Thanks Guys!