turbosquatt

As most of you know, the engine bay on the S4 looks much different to a MT6 owner than to a TIP owner. The existing write-up for replacing the DS EGTs may work for some, but I couldn't do it from the bottom side. So, here is a step by step (without pics,sorry, didn't have my camera) of how I did it. I did everything from the top side...

1. Take off the y-pipe and accordian hose.
2. Remove the coolant tank screws and move the tank forward out of the way.
3. Remove the DS combi valve(silver top, BOV looking thing) hose. You may have to unsnap and remove the heat wrap that surrounds it. No need to remove the valve itself.
4. Remove the 5 allen head screws that secure the secondary air injection pump (black motor with circular bracket right behind the intake mani). There is also one 10mm nut on the side of the bracket next to the after-run thermo switch, loosen it enough to remove the SAI pump bracket.
5. Lift the SAI pump out of the seat and move it to the left out of the way. You may have to remove a couple vacuum hoses from the valve that sits in front of the SAI pump to move it.
6. Remove the two screws that secure the downpipe heat shield. Lift and move the heat shield so you can see the EGTs.
7. Spray the sensor nut with PB blaster, wait 1 minute, and spray it again, and if you feel like it, again and again, as this will make it much easier to break loose.
8. Use a 17mm open end wrench, and if necessary, a breaker bar to loosen the nut.
9. Unscrew the rest of the way with your fingers if you can reach down there. If not, then have fun unscrewing it 1/16 turn at a time.
10. Unclip the sensor harness. (black connector on the back left side of the intake mani, right behind the red connector)
11. Pull the old sensor out, and put the new one in the same way the old one was routed.
12. Put everything back together in reverse order...

Start to finish with the right tools, this should take about an hour and a half. Good luck!

AvantS4me

Good info and write-up, thanks.

S4_NE

nice work and info