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Running lean

5K views 15 replies 8 participants last post by  Stang23 
#1 ·
I just installed bbk shorty headers, bbk catted x pipe, borla atak catback exhaust, jlt series 3 cold air & sct sf3 tuner with custom tune from bama..
Now my check engine light is on & code says I'm running lean??
 
#3 ·
Ok so the simple questions , did all of the O2 sensors get installed back correctly? What about the CAI ? Check the bottom side of the throttle body to make sure the inlet tube is positioned over the lip of the TB. These are two very common things. Next to that you make need your rear O2 sensors turned off with that set of cats. Check with AM
 
#4 ·
Djw05gt,

Sorry to hear you're having issues with the new setup! Lets see if we can trouble shoot this lean code, and make sure it's nothing mechanical.

Have you gotten a chance to over look the exhaust thoroughly and make sure there aren't any leaks? A small exhaust leak between the header flange and down pipe will easily cause a lean code. Also, make sure you re-torque all of the header bolts after a few heat cycles. This is required for any header installation with new gaskets. An exhaust leak could very well be coming through header primary tunes flange, if the bolts haven't been re-torqued.

Also, I'm assuming all 4 of the O2 sensors are plugged in? There should be one before and after each catalytic converter.

Let me know if you've checked these things and if not, give it a try and get back to me after another test drive. Then we'll go from there, depending on what your results are!

Shane
 
#6 ·
Thanks everyone for the advice.. I started with the easiest & checked the cold air & it made the most sense to me because when I installed cold air directions said no more the finger tight on hose clamps & you just can't get a hose clamp very tight with your fingers.. So I tightened with screw driver & engine light has been off for 60 miles
 
#8 ·
Ok the check engine light was off for a bit, but now it is back & it's coming up as a bad cam position sensor.. So I'm liking for more advise? Wasn't really expecting to upgrade my car & the check engine like on every other time I take it out
 
#9 ·
Switch the sensors right for left, clear codes and check again.
 
#13 ·
Which code exactly? It didn't change from left to right or vice versa?
 
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