I just removed my stock air filter box and installed a K&N Cone Air Filter. After I did that, the traction control light and the check engine light came on.

If I replace the original air filter and remove the K&N Cone, will this return everything to normal? I'm assuming I messed up the MAF sensor. Is there a way to fix the problem without removing the cone? Any help would be GREATLY appreciated!!

-Ryan

 

Check and make sure the little vaccum line in the intake tube is still connected.If it comes lose both your check engine and traction light will come on. It's located about 1/2 way between your throttle body and the air box. If you want to reset the ECU just dis-connect the battery for a minute and you should be set.

 

I removed the K&N Cone and replaced the original air filter. Once I did all that and turned the engine on, it was the same story: Trac Light and Check Engine light. After that, I disconnected the battery and both lights are now off. Is it going to stay that way now, or do you think it will come back on later? (i.e. is this just a temporary fix?) Thanks SO much for everyones help!!

 

If it does come back on then you need to check your O2 sensors. Your ECU prob.just noticed a change when you put the cone filter on and set off the warnings. My check engine & traction light came on last week after I did a complete tune up.I left the little vaccum hose off of the intake and after I put it back on,I dis-connected the battery to reset the ecu. It hasn't came back on and I have had no problems.

Good luck

 

After resetting the ECU, I drove for about 10 miles, and once I got on the interstate both the check engine light and the Traction Control light reappeared. Anyone have any advice for me now? I'm afraid I really screwed something up. Help!

 

I took the SC300 into the dealership today. I'm afraid they are gonna want to replace my O2 sensors...I would still appreciate any advice if anyone has any!

 

The dealer will charge you big $$$$ to do that.Any shop can do the same thing and you can get your O2 sensors from an Auto Parts store or online and save some $$$.Changing O2 sensors is not a major job. Call around and get some estimates before turning it over to the dealer.

 

I believe Bosch makes some inexpensive replacement O2 sensors. Good luck

 

If you leave it without doing anything, what other things might happend?

 

I took the car to a local mechanic (Not a Lexus Dealership). They found a small vaccum leak and fixed it for free. Make sure dealerships don't attempt to make you purchase new O2 sensors when the prolem might just be a slight leak!

 

Why do u guys think its O2 sensor? Instead buying new O2, u should do a scan on your car to see why the check engine light along with tract light somes on.

 

It seems that when the trac.light and engine check light come on together the ecu throws a code that say' it's your O2 sensor. But,I can tell you that when my sc did this it was the little vaccum line on the air intake that caused the the lights to come on. Check the little vaccum line fitting(on the air intake) also because it is very easy to break or crack.I didn't notice it when I 1st looked at it but on close inspection I found a crack on the fitting. A little bit of epoxy stuff fixed it right up.

 

i know this is a noob question but... we have trac? when i drop the clutch sometimes no trac light comes on. i just keep on burning rubber...

 

You definitly got an 02 sensor problem. I was down the same road as yourself and it's not cheap to replace. If you don't get Lexus O2 sensors then you have to get aftermarket. Much cheaper and they don't just snap right into our harness you have to splice them in (PAIN IN THE REAR) Spend the extra money buy the real ones and do it yourself. Many people here have done it the other way and they are working fine, I just like to do things the right way cause regardless what people say aftermarket doesn't compare to the original in about 80% of the cases I have witnessed.

 

i agree its the O2