The CEL has come back on twice since the origional post. Both times codes 2(o2 sensor) and 5(egr faulty). It does have 125,000 on the clock. Could a bad oxygen sensor cause the egr code? If it is the o2 sensor, what is the most obvious place to start. How many o2 sensors are on a 1995 e320? Should I replace all of them or is there one that is most prone to failure? There is no noticeable change in the car and when I clear the codes the light might stay off for a couple of hundred miles. When it does come on it usually comes on at a warm start. Thank you again.

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tgmiller77
1997 Land Rover Discovery 158,000
1995 E320 Wagon 132,000mi
1999 E320 Wagon 97,000mi

There's just one O2 sensor. It's a 60k mile item. If you don't know the history of it and you're getting the fault code that's a pretty good place to start. It's fairly easy to replace.

Here's a link to your DTC #5 . . . plugged egr tube. . .
94 e320 EGR tube cleaning How many hours to do?

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Regards . . . . JimF
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'94 S500 Cpe

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