hey guys i am installing a set of 4.10 gears and a set of LTs first thing in the morning. ive heard the gears will make the check engine light come on. is this true and will it efect anything untill a get a chance to tune the code out? i have also gone with the off road set of LTs and will be doing away with the air system. i know this will trip the engine light for sure. dose this effect anything or is it ok to drive untill a tune? i am not taking the car for a tune for about 4 or 5 mothns so i would like to enjoy the headers and gears untill then. the light dose not bother me as long as it will not hurt anything! thanks

 

It shouldnt hurt anything as far as the air removal. Just make sure to not let your connector for the air pump dangle around. As for the gears, it wont(shouldnt) set off a check engine light but your mph will read way wrong. So, you can live with it for a while....wouldnt want to drive forever with your mph being wrong but no harm done. As far as not having cats anymore, you will run rich I believe(dont quote me on that) and it should ONLY affect your mpg a little. But let somebody else chime in on this for you. I am saying my experiences from a 94 lt1 car but with your car being obd2 and having a rear o2 sensor, I may be wrong

 

You will need to get a flash tune for the gears because your speed will be off, and the car will also run pig rich with the headers like that without a tune but it shouldnt hurt anything.

 

cool thanks guys! so how bad of an idea would to be to drive the car running rich for a couple months?

 

Not as bad as running the car LEAN for a couple months.

And yeah, your speedo will be way off, but that won't hurt anything.

 

hp tuners will be able to get rid of the gear light and recalibrate the gears won't it?

 

M6 gear swap should do nothing but mess his speedo up. OP you should probably get a mail order tune for the gears and headers. My 2 cents

 

just thinking about it. call me a super newbie. but y would the headers make the car run rich? shouldnt it make it run lean if anything?

 

when I did headers on my car, I found that the car was close to bang on for it's tune. It just needed to be richened up a small amount, didn't gain me even 5hp with the tune.

The stock tunes for the earlier years will usually be richer than ideal for power. Though it's been noted some factory freaks that are pulling big numbers at stock are on the lean side of the spectrum. If you have a factory freak for HP and torque, I'd recommend getting it checked after the headers are installed for if it's running too lean or rich. The tendency is to lean out.

 

Its not gonna hurt anything... It runs rich just because lol (i dont know why) but a flash tune will be able to do it, some speed shops will do it for at max $20. Your speedo will be way off, if you cant get it flashed for the gears be careful and watch ur speed.