| Author | Message | ||
     p (Pfb) Member Username: Pfb Post Number: 93 Registered: 08-2003 |
'94 Disco V8i. The sevice schedule shows replacing the 02 sensor at 84K miles... Just about what I am at. I'm sure it's more or less a preventative maintenance deal, but what are the symptoms of a failing or faulty O2 Sensor? Do they either work or not, or can you have degradation in performance due to a high mileage sensor? I have been noticing some particularly crappy (yes, even for a disco) gas mileage lately, and it seems like morning first-starts perhaps run a little rich (or perhaps oil fouling?) and need a rev or two to blow the crap out the exhuast... | ||
| Jim Macklow (Macklow) New Member Username: Macklow Post Number: 35 Registered: 03-2003 |
I replaced both of mine at around 150K miles when the onboard computer display showed that my left-side lambda sensor was bad. Take a look through http://www.fourfold.org/LR_FAQ/RR/FAQ.Engines.Fault.Codes.html My bad sensor was black with carbon, the other side was clean. | ||
| Geoff 93 RRC (Geoff) Senior Member Username: Geoff Post Number: 278 Registered: 11-2002 |
Failing o2 sensors often show up as poor gas mileage. They can degrade or not read properly. They will sometimes show up as a code on the ECU LED readout. I also had one side fail completely and it was black with soot while the other was clean. Clean the stepper motor plunger and seat as an initial step on your idling/starting issue. Before you assume failed sensors or some other EFI problem, make sure you have recent tune up parts including air filter and crankcase breathers. Also ensure your vacuum lines are connected and not cracked. Cold temps and winter formulated fuel can cut mileage 20%. |
