i'm having a major problem with my car running rich and slightly lean. i replaced a new o2 that wasn't acting right with another new one and it worked great for one day but now it's acting like the old one and not reading very much.

the O2 itself is very clean which is evident of a lean condition yet the car only seems to have problems when moving from a dead stop at a traffic light or when at a cruise speed like 50. what would this be evident of?

is it possible that my exhaust is to large and the O2 isn't heating up properly? would a 3 wire O2 be my solution??

any helpful suggestions would be greatly appreciated!!

 

I'm experiencing the same problem. Let me know how you fixed it.

Thanks

 

try checking the grds on the backside of the pass cyl head. One is for ecm and the other is the 02 grd.
Later
Jeremy

 

my exhaust is 4" with 1 3/4" primaries.....

i disconnected the O2 and the car ran good with no hesitation or lean misfire??

so i hooked up a 3 wire O2 that we had lying around from a DFI system and it cured things up. still running way to rich as there are some tunning issues but now i can focus more on the chip parameters rather then thinking it's faulty equipment elsewhere.


if TPIS doesn't get it right the second time through i'm going DFI.

thanks guys!!

 

What are the advantages of running a 3 wire O2 sensor?

 

A standard 2 wire O2 begins working at 600 degrees. If moved down the exhaust stream (e.g. header collectors) it may not operate properly. A 3 wire O2 has an ignition wire input to the 3rd terminal to heat it up so it works better.

 

What 3 wire O2 sensor should I purchase for my 88 Iroc 305 with the following mods:
Paxton Supercharger
Nos 100 shot
Every bolt on from the 52mm throttle body to the Flowmaster exhaust without having to remove the heads.

All feedback is welcome.

Thanks