New C4 Exhaust System - More Bark With Your Bite, Part 1

Even with the stand-off tube, the fit was so snug that we had to grind off the integral washer until it was even with the hex.

As long as we were changing out the whole exhaust system, we chose to install a new Bosch oxygen sensor. While these sensors are usually thought of as being expensive, ours was only $21!

It's no surprise that twenty-year-old plastic that's been heat-cycled a zillion times is brittle. The lock tab broke off this O2 sensor wire connector when we disassembled it, so we used a plastic tie to hold the connection together to prevent future problems.

You can see that the hose from the oil filter is just too close to the header tube on the driver side. We ended up using several 90-degree adapters and hose clamps to position the hose away from the header tube until we decide on a more professional-looking solution.

In the course of our work, we found the speedometer sensor at the rear of the transmission was leaking. With the exhaust system removed, this was the logical time to repair this simple problem.

Just one bolt holds the clamp on the speedo sensor. With the clamp out of the way, the sensor pulls right out.

The fix was as simple as replacing the O-ring on the sensor. Three cautions here: lube the new O-ring so it slides into the transmission more easily; be careful not to nick the O-ring; and be careful when removing the unit so the speedometer gear does not fall off inside the transmission.

We found we had to bend this lower heat shield on the passenger side in order to keep it from vibrating against the header.

This is the functional, but not very pretty, temporary solution to the interference problem with the hose on the driver side that carries coolant from the engine block to the oil cooler, which is part of the oil filter adapter. A more sanitary solution is in the works.