jjwalker

I would like to disable the AWS system, BUT keep the ECU happy. I don't like driving around with a check engine light.

I got an idea from an old FD mailing list that said something about putting a plug in the hose, but never heard of such a thing anywhere else.

So, Can I just plug the damn hose and be done with it?

wthdidusay82

iTrader: (15)

There are no check engine lights/codes associated with removing the aws that I know of on series 4, not sure about series 5.

The lights you refer to are dummy lights that tell you things you should already know if you keep an eye on everything often.

The most important being the low coolant and low oil lights.

jjwalker

It throws code 38 on an S5 if you unplug it.

wthdidusay82

iTrader: (15)

Another reason I always liked having an s4. Lol

jjwalker

I am not getting many responses, so i guess i might just try it and post up.

As far as I know, this is how it works...

AWS solenoid opens and draws in more air so the MAP shows less vacuum, so ECU adds more fuel. Same goes for the AFM opening up a bit.

I did a little test by opening up my secondaries without moving the TPS, and the engine speed increased without issue. It's like it sees more air and just adds more fuel, even though the TPS hasn't moved.

I think this will work as long as the ECU sees the solenoid open and close, I don't think it checks are cares about anything else. Also, the FSM and other sources just say code 38 is open circuit or wiring issues between solenoid and ECU.

MMoore4545

iTrader: (7)

So here's a thread where I hashed a lot of aws system out a while ago: https://www.rx7club.com/2nd-generati...isable-969496/

to paraphrase it: Aws isn't just fed by the aws solenoid on our cars, it is also fed by the bac valve. And unplugging or removing the solenoid doesn't do much.


You're right the TPS isn't always needed for the engine to compensate for rpm/air changes, think of how the electrical load system works and how the map or "pressure sensor" and maf work together when ecu tells the bac valve to open to compensate for the rpm dropping due to additional alternator load.

That system is pretty much reactive and doesn't cope well with big air volume changes (leaves a brief moment of lean), which is why the TPS is used for larger changes/under load, because it is predictive and compensates for that lean moment.

jjwalker

Here is why i want to get rid of it. Number one, it cant be good to suddenly rev to 3k right at startup, so when I start the car, I start it in gear.

I have a remote start now and when I use it, I am not in the car to disable the system.

I will try plugging it and see what happens. If that doesn't satisfy me, I may do electrical trickery.

I was also thinking that I could program an output on my RS brain to "trick" the ECU that it is in gear when I remote start. If it came to this, is there any negative consequence?

satch

iTrader: (1)

^ The idea that the BAC plays a role is very telling. I've unplugged my Air Bypass (S4) and the high idle rev upon startup still occured. It wasn't until I unplugged the BAC as well was I able to defeat the system. On an S4 you can defeat the process but I'm not sure it is the same for the S5. On an S4 you can unplug the temp switch screwed into the radiator and this prevents the high idle rev from occuring, but it can affect how the car idles until it completely warms up.

jjwalker

Well, what do yall think about tricking my ECU to think it's in gear with a programmable output from my RS brain.

It's a compustar, so I have 10 programmable outputs to play with.

I would program the output to only deceive the ECU until I do key takeover and drive off with it.

MMoore4545

iTrader: (7)

Yea, S4 gets an easy fix with the simple temp on/off switch that is screwed into the bottom of the radiator. S5 however, does not have the sensor, and is a little less tamperable.

Give it a shot with the programming.

I'd say make the neutral switch your target. (the plug on the passenger side of the transmission) BUT. If your avatar is your car the convertible top won't operate if the neutral switch doesn't see neutral.

I don't know what programming options you have but maybe disable the neutral switch from key on to start tricking it into thinking it is in gear, and then let it resume working normally..

Also this programmer would have to see continuous power from key on and not be disabled when you turn the key during startup.

-M


Edit:

Personally if I had kept the factory electronics I would have probably bypassed the neutral switch on the transmission and wired up a single or dual terminal switch. Keep the switch flicked "in gear" until I needed to operate my top. Some could consider this ghetto, but it would be a simple hide able solution.

jjwalker

It's not a programmer, it's an alarm, remote start and keyless.

That was my plan, to trick the car into being in gear when the remote start activates. I can program it to stop tricking the ECU when I put the key in and take over the remote start.