I was wondering where the 02sensor is located on a 5th gen prelude as well as how to check to see if it is working properly. pictures would be appreciated as well.

 

They're pretty much directly below the gear shift/radio area. They are the only things that plug into the exhaust, you really can't miss them. If you are stock, then your secondary O2 sensor will be plugged into the catalytic converter (unlike mine). The primary O2 sensor will be closer to the front of the car, the secondary O2 sensor will be closer to the rear.

 

that helps quite a bit thanks..also if the sensor was not functioning properly it would throw a code i would assume indicating the need of a replacement.

 

Correct. And the code should indicate which sensor is faulty. Take it to AutoWeDontKnowShitZone to have the code pulled for free. (other auto parts stores also do this for free)

 

well to make a long story short ive had a bad hesitation issue with my car but it only occurs when the weather is warm. At night or when its cold(less humid i suppose) my car runs exactly as it should..its been like this since i bought it.

So after a solid 10 hours of research and doing a complete tune up, ive decided to switch to a p28 chipped which apparently has helped many other with this issue.

 

O2 sensor could cause that hesitation. I'd do as kronn said though and get it tested before you just start swaping parts.

The p28 chipped might not be a great idea though. You should have it tuned properly if you can afford it.

 

whats the easiest way to have the 02 sensor checked, i mean i could put the car on a hoist but i wouldnt have the slightest clue if it was malfunctioning, and as kronn said it would through a code if it wasnt....which makes sense.


I also think it might have something to do with the bolt-ons that the previous owner installed...(short ram, exhaust) I hear that if u install and boltons you should have it retuned afterwards?!?

 

You can't just tune our cars. But with just simple intake and exhaust, it'd be close to pointless anyway. If you have no intentions of heavily modifying your car, the only "tune" I'd suggest is a piggyback like VAFC. I'll have dynos this Friday to show its effectiveness or lack there of.

 

#18 is the front (primary) O2 sensor (bank 1 sensor 1) it is screwed into the downpipe/flexpipe before the cat, and #19 is the rear (secondary) O2 sensor (bank 1 sensor 2) it is screwed into the rear of the cat.