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I have removed the cats off my Turbo S5 and now Im looking at removing the Air pump. IS there anything to know when doing this? Will it affect my idle or drivability? Still on stock ECU will I need the block off plates? Should I go ahead and delete the EGR?
Your idle will be affected by removing all the air pump stuff. However, you can easily adjust it with the idle adjust screw on the BAC solenoid assembly. There is no need to adjust the throttle body. If the throttle body is still correct, don't touch it at all. The idle air screw on the side of the BAC is all you need, just follow the procedure in the FSM, pages F2-15,16.
When putting on the block off plates, you can seal those with some rtv if you want something permanent. If you want to make your block off plates look clean, you can remove the studs and just put in bolts. When you get rid of the EGR assembly, you can either choose to T off the vacuum line for the BOV for your MAP sensor, or you can do what I did and add a vacuum port to your block off plate. This maintains the original vacuum port for the MAF and you don't have to T anything. I have no idea if it makes a difference which rotor the MAP is connected to, but the original port passed through to R1. BOV is on R2.
Port added back to block off plate for MAP sensor.
This is pretty straightforward. With the absence of the EGR stuff, your ecu will read error codes 30 and 33. These will only show up when reading the codes though, not normal operation. It does not affect regular operation.
The only thing I can think of that will bug you is that your waterpump belt will only be on one side now instead of a belt being on both sides of the waterpump pulley. At high revs, it'll squeal like a pig. If you can leave your pump or figure out an idler pulley, that will solve the squeal issue.
Your idle will be affected by removing all the air pump stuff. However, you can easily adjust it with the idle adjust screw on the BAC solenoid assembly. There is no need to adjust the throttle body. If the throttle body is still correct, don't touch it at all. The idle air screw on the side of the BAC is all you need, just follow the procedure in the FSM, pages F2-15,16.
When putting on the block off plates, you can seal those with some rtv if you want something permanent. If you want to make your block off plates look clean, you can remove the studs and just put in bolts. When you get rid of the EGR assembly, you can either choose to T off the vacuum line for the BOV for your MAP sensor, or you can do what I did and add a vacuum port to your block off plate. This maintains the original vacuum port for the MAF and you don't have to T anything. I have no idea if it makes a difference which rotor the MAP is connected to, but the original port passed through to R1. BOV is on R2.
Port added back to block off plate for MAP sensor.
This is pretty straightforward. With the absence of the EGR stuff, your ecu will read error codes 30 and 33. These will only show up when reading the codes though, not normal operation. It does not affect regular operation.
The only thing I can think of that will bug you is that your waterpump belt will only be on one side now instead of a belt being on both sides of the waterpump pulley. At high revs, it'll squeal like a pig. If you can leave your pump or figure out an idler pulley, that will solve the squeal issue.
S5's I dont think have EGR valves. I will probably go with a dual alt pulley from bonzai racing.
