O2 Problem/Question
Thread Starter
TECH Fanatic
iTrader: (11)
Joined: Dec 2004
Posts: 1,790
Likes: 0
From: Dragging 408's
O2 Problem/Question Ok ...So I have been logging my car at WOT and checking for KR and when we go over the log the Drvr side O2 bank goes way lean like in the 50's while the pass side stays pretty steady at 890's.. Only for very short instances...Anyone have any Idea what this could be ?
An intermittent miss will cause the O2 reading to temporarily skyrocket.
When the cylinder doesn't fire it is just injecting a full slug of fresh oxygen into the exhaust. This will cause the O2 sensor to read REALLY high.
Does the car feel like it has a miss?
When the cylinder doesn't fire it is just injecting a full slug of fresh oxygen into the exhaust. This will cause the O2 sensor to read REALLY high.
Does the car feel like it has a miss?
Thread Starter
TECH Fanatic
iTrader: (11)
Joined: Dec 2004
Posts: 1,790
Likes: 0
From: Dragging 408's
Originally Posted by NoGo
An intermittent miss will cause the O2 reading to temporarily skyrocket.
When the cylinder doesn't fire it is just injecting a full slug of fresh oxygen into the exhaust. This will cause the O2 sensor to read REALLY high.
Does the car feel like it has a miss?
When the cylinder doesn't fire it is just injecting a full slug of fresh oxygen into the exhaust. This will cause the O2 sensor to read REALLY high.
Does the car feel like it has a miss?
Take your car to a dyno shop. Don't go to a loaded dyno (ie dynapack, mustang dyno), go to a regular unloaded dynojet dyno.
Put a wideband in the exhaust. See if the wideband reading corresponds to your O2 sensor lean spikes. If so, you probably have a miss or valve float etc... If not, I wouldn't seat the spike too much as long as your car runs okay.
If you have a miss you will see it on the dyno chart. Ensure that you have 0 KR during the run. Put the dyno chart smoothing to 0. If you have a miss your dyno chart will look jagged with 5-10 HP sharp dips during the miss. This is easy to see with an M6, but still pertinant with an Auto.
It is also MUCH easier to feel misses during a dyno run.
Put a wideband in the exhaust. See if the wideband reading corresponds to your O2 sensor lean spikes. If so, you probably have a miss or valve float etc... If not, I wouldn't seat the spike too much as long as your car runs okay.
If you have a miss you will see it on the dyno chart. Ensure that you have 0 KR during the run. Put the dyno chart smoothing to 0. If you have a miss your dyno chart will look jagged with 5-10 HP sharp dips during the miss. This is easy to see with an M6, but still pertinant with an Auto.
It is also MUCH easier to feel misses during a dyno run.
