I have been getting a code 13 lately when in higher rpms. Have had my headers on for almost 5 months now. When my check engine light comes on it almost always goes out a few seconds later but sometimes it takes a bit longer. 10 15 seconds. How can I fix this? New o2 sensor? Or is there more to it.

 

http://www.chevythunder.com/o2_sensor_diagnostics.htm

 

I guess I could buy a new one if it's faulty. Has been on there for quite some time. I read on a thread something about a heated sensor but don't quite remember.

 

You can add a 3 wire delco Afs-74. With headers the o2 can cool off and not go into closed loop. This usually happens at idle though.

 

Yeah the code comes on when in higher rpms. So maybe it's too rich or something?

 

Are you getting a code 45 ?
A new o2 is cheap and easy to start with.

 

but if you're going to buy a new 02 sensor, you might want to go ahead and get a heated one.

 

Why the heated one? Have a part no.?

 

Amazon, acdelco afs-74 . It will warm up faster for closed loop operation.
you can hook the power wire to fuel pump wire at the relay.

https://www.ebay.com/itm/TPI-TBI-3-W...AAAOSwJcZWcLb5

 

like tuned said "With headers the o2 can cool off and not go into closed loop. This usually happens at idle though."

a heated 02 sensor gets it and keeps it up to temp and in closed loop where you want it.