updated, need more help?


Can anyone tell me why my car runs very rich all of a sudden, it had headers and I replaced them with another set of longtubes. Now all of a sudden my car is running rich as to where on full throttle im at 12.2-12.7 afr. Before I used to be near 13.5afr. So why would changing LTH with another set of LTheaders have anything to do with it?
Everything is hooked up still and it runs fine otherwise and no vacuum leaks to what I can think of? I just dont know, help please
thanks, Tom

 

does anyone know this?

 

if your running the same 02's as you did when you installed the long tubes id look at them first. sometimes when running new headers. especially coated ones. theyll fry your o2's on initial break in

edit : only buy acdelco o2's!!!

 

Beat me to it. OP, check you o2's.

 

me = win

 

Yes...one thing you forgot...

OP, check for exhaust leaks, fresh air hitting the o2's will cause you to run rich.

SoxXpupPeT, no we're 1-1 LOL.

 

you have outdone me this time mr. ss.slp... touche!

 

Yes sir any unmetered air getting into the exhaust such as header leaks or holes of any kind before the 02 sensor will make it run rich. Also might throw a code as well.

 

anyone else have any clues to what is going on? As of right now I checked my car and headers are not leaking as to what I can tell. There is silicone and gaskets for the headers and it all seems to be fine. I have swapped o2 sensors and the problem still persists. So I have no clue to what the hell this can be, im lost right now and very upset. This car rarely gets driven and it would have been nice to drive it. At w.o.t it goes to 12.6-12.8afr and should be around 13.5 afr like it used to be. Could the tune have gone away and all of a sudden I have noticed my fuel pressure increase as well it went up 2 psi???? wtf I have no clue, any help would be greatly appreciated.
thanks,Tom

 

anyone, Im stumbled??