I have a 99 Prelude and it threw a check engine light. I took it to the dealer and they said they couldn't find anything, but the sensor was slow to respond. They cleared out the check engine light. The dealer also stated that it may be from my aftermarket exhaust. I've had the tanabe exhaust on for about two years now. It never threw a check engine light until now. The dealer also stated that a new O2 sensor costs about 340 dollars!

What does the O2 sensor do and is it a critical component? Will my car get damaged if I continue to drive it with a bad sensor?? Any help will be much appreciated!!

 

if it throws a code that puts the car in "limp" mode. It'll run like ***, but it'll be safe.

It might've just been a random code. I'd wait to see if it comes back. If it does, then I have some tricks that I just learned that might help you out.

 

The O2 sensor going bad has nothing to do with the cat-back portion of the exhaust. The dealer is full of sh*t if that's what they are claiming. Your car has 2 O2 sensors. One is in the A-pipe collector. The other is in the cat-converter. Since both are monitoring exhuast before it ever reaches your Tanabe Cat-back, there is no way for the dealer to blame your exhaust for this problem. It should be covered under warranty. (Although if you have an aftermarket header, the dealer may have a slightly more legitimate case to deny this claim...)

Andrew

 

my car is out of warranty. In fact, it just ran out a couple of months ago. The light is back on again. If I have to replace it, what is the best route to go? Is it something that's a pain in the *** to do? Any help would be much appreciated...

 

It's not that hard to replace. You'll need to get the car up on jacks. The primary o2 sensor is before the cat on the muffler. You just unplug the wires unscrew the sensor. Screw in the new sensor and plug it in. The only problem you're going to have is getting the old one off. Sometimes pulling them off can be a real hassle. With a 98 you should be okay. Be sure and get anti-seize from an auto store and apply it to the threads of the new O2 sensor before putting it in.

You can order the sensor from hondaautomotiveparts.com or some place like that for relatively cheap.

 

thanks for the tips!!

I'm probably going to be doing this fix myself. Any tips besides the one's that were mentioned would be helpful. I've never done the work myself on the prelude. I'm doing everything now that I got the M3. Don't want to get ripped off at the dealer.

If any tech heads know this answer:
What does the O2 sensor do?