scanmaster 02 readings?

[TA49-WE4]

Just wondering why when im driving down the highway with the cruse on and then kick it off that the 02 readings go to 000 and stay there for several frames. It will do this in town also when your just crusing and let off the gas to coast. Doesn't do it all the time but every once and awhile. I changed the 02 and it didn't go away. Any ideas? this is on a 87 turbo t.

 

[stickybones]

It's normal. It's the DFCO (decelleration fuel cut off) activating. When you lift off the throttle, the ECM momentarily cuts off fuel until certain parameters are reached. Search for it and you'll find more. BTW, if this is the reason you changed your O2 sensor, you might want to hold onto the old one since it's probably still good.

 

[TA49-WE4]

Thank You for the info stickbones. I'll keep the old 02 as a spare.