[mrnickleye]

Trust me (see my profile), you can get an aftermarket 3-wire 02 for about $75. Bosch is the most popular at the parts houses. You can get one with the oem plug already on to just plug-n-play.

You may want to spray some WD40 (or similar) on the threads a few times and hours before removing it.

If your mech. said fuel 'lines', (carboned up) get a new mechanic, he IS ripping you off, cause that just won't happen. Also, we only charge $65 labor to replace the 02. (and we also re-check everything to make sure you are gonna pass the test).

It is very true that carbon builds up on the inside of the intake manifold. This is due MOSTLY from the EGR system feeding exhaust gasses into the manifold. It also builds up on the intake valves.

Maybe he meant that the carbon is built up in the egr passages, and therefore the egr system is not working, and will cause the NOx to be too high.

I would ask around (friends, family, co-workers, grocery store clerks, etc) for a recommended shop to check out your car, and make some of the repairs if you can't. Cleaning the egr passages is work, but easy, but does take some mechanical skill, and knowing what to remove and clean.

If you idle is high, you WILL fail the test. That sounds like other issues. How do you drive with that??