TBI: 3 wire O2 sensor and having a chipped burned.

[mr.smartass]

I have an '89 K5 with a TBI 350, Since I put my reman motor into my blazer it has had problems idling sometimes surging at red lights and stop signs and rpms surging up and down while in park, sometimes even dying plus the idle was very high at startup. I had a slight timing problem that i worked out (the guy who put the motor in advanced it 4 degrees) so now the idle is down but you can still feel it surging, it runs fine going down the road but the idle really bugs the hell out of me. I did put a small cam in it when the motor went in but i didn't think it was big enough to affect anything... but according to my mechanic (not the guy who put the motor in) the o2 sensor isn't staying hot enough at idle and i might need a chip burned, can anyone help me out with what type of O2 sensor i need to get, maybe a part number and how to wire it up, plus who can burn me a chip? thanks.

 

[1979jimmy350]

check for intake leaks also, that can cause the surging, use a can of carb cleaner and spray around the intake gaskets and base of the TBI if the engine rpms change while doing this you have a vaccum leak

 

[dyeager535]

AFS-74 is the 3 wire O2 sensor recommended.

Did you go with headers or something? If you didn't move the O2 from stock location, you really shouldn't need a heated O2 sensor, although they can and will drop out of closed loop at idle sometimes, even with manifolds.

Edit: Don't cheap out on O2 sensors. Get a Delco. <-and that's a period

 

[lamberthkp]

go to www.tbichips.com this guy can make you one cheap. im having the same problem as you right now just need to get my chip.

 

[mr.smartass]

yeah i meant to mention i do have headers, that's why i was asking about the 3 wire O2 sensor. Does anyone know how to wire it up??

 

[southernspeed]

You're standard purple wire still goes to the O2 sensor, the other 2 are switched live and earth....simple!

 

[mr.smartass]

oh... so simple lol thanks i hope this fixes most of my problem.