I just put in my new-er motor. I can't manage to have the car to idle without me on the gas pedal. It idle by itself a couple times, but the car idles at 5k rpm. Can it be vaccum leaks, if so, im go n to take off the vaccum lines and plug them all up.

Umm.. The vacuum lines serve a purpose.. Are you using a stock ECU?

THIS IS ASSUMING YOU HAVE A TURBO, THE INFO IS THE SAME FOR N/A BUT THINGS MAY BE IN DIFFERENT LOCATIONS



Check and set your TPS, and check your idle stop/set screw.



The idle set screw is on the firewall side of the TB. It is a small threaded shaft with a slit for a straight blade screwdriver to fit, it should have a locknut on it as well. It is located close to the body of the TB and serves to stop the throttle plates via stopping the throttle linkage.



To properly set the screw you should turn it out all the way until it isnt touching the stop plate (follow the end of the screw it hits a plate on the throttle linkage effectively stopping it from moving) When you can see air between the screw and plate it is ready to be set. Move the screw until it is just touching the plate. Now turn it 1-2 full revolutions that should set it to idle around 550-1000rpm. If this screw is screwed far in that is your idle problem. If not leave it set liek I said and move onto the TPS.



Checking and setting the TPS can be done using the topic in the "2nd Gen FAQ" forum which you can get to by clicking on its name in the main "2nd Gen Specific" forum. You may also want to check ivf your TPS even works correctly, that info can be found in the FAQ as well.



For an S5 you may want to read what i wrote in that FAQ topic as the green plug is in a different location (you'll need to build an LED check light and plug it into this location) and you dont need to ground the other green plug.



If you'd like me to go into more detail on setting the TPS post asking and I will take pictures and write down everything you need to know.



If after doing these two things your idle is still bad I'll need more info:



A) Is your AWS connected properly or have you removed/bypassed it. (accelerated warmup system, it is a solenoid to the left of the TMIC with a line from the TMIC running to it, and then a line running from it to the UIM, i believe and it has an electrical connector as well)



B) Is your BACV still connected and plugged in, or have you bypassed/removed this? (Bypass Air Control Valve, has an electrical connection on it, is a mounting spot for the coolant lines running to the TB and should have a connection coming from just above the turbo, assuming you have a turbo, and the BACV itself mounts onto the UIM)



if all those things check out there are a few other possibilities, such as stuck throttle cables etc.



kevin.

Thanx teknic. I ll go ck on it in the morning ANd tell you how it went