Does anyone have a picture of the plug I need to jumper to set my idle speed screw?

Is it the green 2 pin with the orange wire running to it?

if it is, am I able to just ground out the orange cable because for whatever reason the previous owner cut that connector off and I’m not sure what they did with the other wire that would connect into it

 

Here you go... The black/yellow might just be a ground wire. It is best to use a jumper with lugs on it. I struggled a bit with thin gauged wire by itself. I need to make a lugged wire. For now, a piece of 10awg seems to stay in place well.
You will likely have to go back and forth between this and setting the TPS. Check your timing too.

 

According to your profile, you have an S5 model. The initial set connector is a green one pin connector next to the battery box. Ground it. It disables the BAC valve. The S4 is different. Always specific what series car you have.

 

Yeah late at night, totally forgot. Unusually pretty good at putting the car in the post, oops. But yes it’s an S5 vert. So just grounding out the orange wire should work for me? Here’s a picture of what I’m working with

Orange wire on the left is where the connector should be attached

 

Also just got my timing dialed in, found the nut that holds its adjustment had come loose and had been causing all sorts of issues. Got that readjust and now the car idles around 400rpm when warmed up. I can’t believe it doesn’t die idling that low, but still something I need to fix

 

Mine does the same low idle situation, occasionally. I have read threads until my head is about to pop. If it is a steady low idle, your are in a different situation.
I solved most of mine just setting the TPS and idle, over and over again. Disconnecting the BAC did help to settle things out. Then connecting it again. Even though the jumper disables the BAC.

I have a feeling that the idle adjust will not adjust it high enough for you. It will be interesting to see what happens. Report back with the solution, if you have one. Thanks!

 

Finally figured this out and it was kinda stupid. The E fan i recently put it is drawing power even when off, and also draws way too much. Not sure why it’s pulling power when off, looking through the wiring I’m not sure how it’s possible. Only thing I can think of is the coolant temp sensor switch and relay I’m using are from a parts car and who knows how old they are.

But simply by unplugging the e fan, my idle goes from 200-300 right back to 750

Gotta love the headache of these cars

 

What’s interesting is it doesn’t drain the battery when the cars off. I hadn’t started it all week and the battery was just fine

i figured if it’s pulling power when the fan is off then it would be some sort of power draining issue but doesn’t seem like that’s the case

 

Good to know you have it sorted now. It seems the relay is wired to your 'key on'. Many do this because having a running fan after you shut the car off is undesirable. Kind of surprised the BAC doesn't compensate for that. What happens when you have the e-fan off at idle and accessories turned on, like the lights, etc? That should verify if the BAC is working correctly. If you have a BAC?

 

The idle doesn’t change from 750 with lights or heat on, the car has no AC to check with

The BAC is in the car, however the air pump is not so I’m not sure if it’s even doing anything. From what I’ve gathered the air pump is supposed to be what helps the BAC activate

 

I’ve been trying to recreate the issue with the fan and am realizing that may not be my issue. I couldn’t get it to jump back up to 750 just by unplugging, seems to only want to stick around that rpm when the car is cold.

At temp, I tried readjusting the idle screw. I opened it all the way and it would idle at about 1500 smoothly. I could then slowly turn it down till around 1100 to 1000 where it would then suddenly drop to the 300 ish rpm

I did this with both the fan plugged in and unplugged, no difference

I disconnected my BAC and tried to crank the heat, this pretty much instantly killed the car so I’d assume it is somewhat working

I might just have to accept a high idle unfortunately

 

I will give you a bump. Hopefully, it will get some more eyes on the thread.

I settled my idle issues to a great degree by going back and forth between the TPS set, idle set and verify the timing. This was a fairly tedious process. It was hard to find the correct settling point as it would change and still does, at times. Kicking down to 400rpm sometimes. It idles very steady at 400, too.

One thing that I haven't checked is the fuel trim screw. It is glued shut from the factory. I am not comfortable setting that.

I am very curious to now if the fuel delivery is being altered at times to be out of spec causing idle issues that we are having. I assume that is is a misbehaving sensor somewhere. Or a misbehaving ECU with a cold solider joint that causes a sensor to work and then not or generally misbehave.

It might be worth having someone put new caps in my spare ECU to see if there is any changes with an ECU swap?

Edit: Just a side note, but an important one, if you haven't cleaned up your grounds, I would do that before chasing this to much further.

 

There's no connection between the air pump and the BAC valve. The BAC is solenoid valve controlled by the ECU. Its purpose is to bypass air around the throttle body to give the idle a boost when there's a load on the engine.