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SolidWorks Mike · 10-08-2012, 08:39 AM

Last week I picked up a set of the Top Speed bypass pipes for my 1997 2.5L Base model. Yesterday I took a look under the car to plan out the install and noticed something I hadn't before ordering them, both O2 sensors are mounted to the mid pipe/ cat pipe. The Top Speed bypass pipe only has one O2 sensor mounting point.

So my assumption is that they simply want you to leave the other O2 sensor off the car. This of course would produce a check engine light so I thought what if there was a second mounting point on the bypass? After some research is seems that on the early models that had a single cat, the system looks for a different reading between the O2 sensors since one is before the cat, and the second one is after, therefor creating a different reading from both. Being a straight pipe, this wouldn't work.

The other options seem to be to accept the check engine light and ignore it, but then what happens when you get a check engine light from something else, you won't know.

Someone also mentioned flashing the cars computer, but that's a bit too far for me.

So has anyone in the same situation come up with a different work around that leaves both the computer and check engine light in tact?

10-08-2012, 08:39 AM	#1
SolidWorks Mike Registered User Join Date: Aug 2012 Location: Las Vegas Posts: 78	Top Speed Bypass Pipes For 2.5L Last week I picked up a set of the Top Speed bypass pipes for my 1997 2.5L Base model. Yesterday I took a look under the car to plan out the install and noticed something I hadn't before ordering them, both O2 sensors are mounted to the mid pipe/ cat pipe. The Top Speed bypass pipe only has one O2 sensor mounting point. So my assumption is that they simply want you to leave the other O2 sensor off the car. This of course would produce a check engine light so I thought what if there was a second mounting point on the bypass? After some research is seems that on the early models that had a single cat, the system looks for a different reading between the O2 sensors since one is before the cat, and the second one is after, therefor creating a different reading from both. Being a straight pipe, this wouldn't work. The other options seem to be to accept the check engine light and ignore it, but then what happens when you get a check engine light from something else, you won't know. Someone also mentioned flashing the cars computer, but that's a bit too far for me. So has anyone in the same situation come up with a different work around that leaves both the computer and check engine light in tact?