S5 error codes help
 

i got error code
30 solenoid valve=split air bypass
33 Solenoid valve= port air bypass
51 Air pump (resistor) relay

What should i check first, i don't know much of these part
91 n/a manual transmission

Code 51 is the Fuel pump and resistor relay and not as how you labeled it. Is your car running okay or are you having hesitation issues when under load?

The other two codes are emission related. Have you removed part or all of the emissions equipment? I believe they are both part of the ACV.

oh my bad, i meant to write fuel pump (resistor) relay
my car is running well, and not removed any emission parts, car is stock and original

Locate the Air Control Vlave on your car and see if the wiring is intact or perhaps burned or severed (damaged in some way).

the air control valve is connected correctly, i might have to remove it an test if it still opens up correctly, or i might have to buy a new one

The error codes only tell you if the voltage readings to the two solenoids are correct or not and not if the ACV works or not as the ECU does not receive that type of feedback information. The front solenoid at the ACV is the Port Air Solenoid which has two wires. One is Black/White while the other is Blue. The Blue wire has idle voltage of 2 volts (this ocurs if the mileage is between 20k and 100k, if the mileage is between 100k and 120k then the voltage at idle is 12 volts, if greater than 120k then it is 2 volts) and w/engine rpm above 3500 it is 12 volts. The Split Air Solenoid, closest to the firewall, also has two wires where one is Black/White and the other Blue/Red. The Blue/Red wire has 12 volts in gears 1 through 4 and when in 5th gear it is 2 volts.

Ok so I hate to hop in this thread but I think I'm having that code 51 issue, ehat should I do to fix it, I'm a FNG sorry

The device which is throwing the code is responsible for boosting the voltage to the fuel pump when the engine is under load. Are you having problems w/the car hesitating or lagging under acceleration for if not then you could just leave it be until the performance of the car is hindered.

I can only push the throttle down about halfway, if I go any farther down then the car bogs down, it just wants to cut out until I back off the throttle

The Fuel Pump Relay has one plug w/six wires. Three are Blue/red, two are Blue/Green and I think the last wire is Green/Red but the relevant wires are the other five wires. So disconnect this plug and jumper one of the Blue/Red wires to one of the Blue/Green wires and this will bypass the relay.

I was looking For that today and couldn't spot it, any pics would really help me out.

It's under the AFM.

Your gunna hate me but what's that? I'm. Not very car savvy sorry lol

The intake duct (large black plastic tube) from the throttle body drops down and goes under the air box (houses the air filter) and connects to the AFM.

ok so the PO took out the stock box and put in a CAI cone. So do I even have a AFM? I'm still confused and hate to be a burden.

The air filter you have connects to the AFM. The relay you are looking for has the one plug as mentioned w/the six wires as mentioned. Since there is only one plug in the car w/those six wires and this device is to be located under where the air box is or went it should not be too difficult to find the relay.

Ohhh ok, I found it haha sorry about that. So now I jumper one of the blue/red to a blue/green and that's it?

Yes, and leave it unplugged after you select the two wires to be jumpered ( a Blue/Green wire to one of the Blue//Reds gets jumpered).