Preventative maintenance?

2000 XJ /4.0/ Auto/4WD /194K DD

Jeep has had all of the routine problems and fixes. RMS/Wheel & Carrier Bearings/ Oil seals Etc.
Throttle body and IAC have been cleaned several times. runs great except for the occasional hot start cyl 3 misfire issue.
All of the engine sensors are original equipment.

Should I look at replacing sensors as a preventative measure?

Joe

Don't replace sensors that aren't broke. They shouldn't wear out. A possible exception to this is the O2 sensors, but I'd run 'em until you get an error code.

i would replace or keep a spare cps as it is a no start sensor. you may want to inspect/clean the nss as it can also be a no start item.

as for other sensors, i would hold off until you get a CEL or you see a drop in gas mileage.

i can understand preventive maintenance, especially since i own an 89, but as long as you do routine maintenance on the wear items(plugs, filters, brakes,...) and fluids, it can get expensive swapping out good sensors and some aftermarket sensors arnt as good a oem sensors.

In my experience the o2 sensor will be bad way before any code shows up--change it based on "per miles" as recommended in the owners manual.

Hallo. You can do some measurements with a DMM.
When a sensor is a little bit broken ,it will not give a cel.

wim

"Most" sensors will not leave you by the side of the road or trail, with the exception of the crankshaft position sensor.

Economics dictate that most people replace the sensors as needed/when symptomatic or when CEL alerts you to an out of spec condition.