Well, it really has nothing to do with age....just the designated market. Mine is a '92 3.0 and did not come equipped with one. It was purchased here in Arkansas by the PO. CA model 22re's also came equipped with them.

Without that sensor, if the EGR malfunctions, it will manifest in another code....like 5 or 25 or 26, blah, blah, blah...because it will affect other components and functions.

I do have a plethora of others links describing the whole EGR system, if you want to frizzle fry some more brain stem cells in your learning.

 

I have a 95 CA spec 3vze. About 6 months after I bought it used the 71 code came on. Replaced modulator, vacuum lines, cleaned EGR passages, removed intake, cleaned it, replaced psv (psp, pcp, vsv ,wtf) valve (the one under the back of the intake), replaced temp sender. Even went ot the dealer and an independent shop, both said they will usually delete or defeat the system either way passes sniff test just fine. Finally tricked sensor w/ $.10 radio shack resistor, walla. Do a search for the proper resistance.

Never, ever, ever noticed a change in mpg, torque or overall performance. I have driven it with and without the CEL from sea level to 5000' rain, shine, heat, cold, snow or sand storms and unlike when I had my jeep, I always made it home.

 

sensor of course

i'll change it tomorrow and look for a way to test the EGR temp sensor also...any change in how it runs will be posted