2002 mercury villager estate. Have been having o2 sensor ...

Hello, my name is \*\*\*\*\* \*\*\*\*\* I'm sorry your having problems with this vehicle so I'll try to help you with this issue.The website may prompt if you want a call, but that would be up to you. So there are many different O2 codes do you know what they sre by the # ?

Its the Sensor 1 bank 1

Also have you had a [timing belt](/topics-timing-belt-ford/) done to it lately?

No hold on I'm going to van

do you know where the clunking noise is coming from as in from the egine , or the [exhaust](/topics-exhaust-ford/) or the belt area ?

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I know that but why the clunk when she tried to turn over then she starts. [Starter](/topics-starter-ford/)? Timing belt?

Good morning This sounds like the starter engagement is giving you the clunk. I would suspect the starter motor itself. Roy

Ok now all of a sudden it has not done it all day. Like it is fixed. Still need to get sensor 1 but that would not cause clunk

No, it will not. Roy