Why cant I run my M52 in OBD2 configuration on my swap?

[jrez]

Im not running cats or the post cat O2 sensors, or air pump. My info is that the post cat o2's are there strictly to monitor cat performance, with no effect on engine performance. You do however apparently lose the closed loop function at cruise with the parts missing(plus trigger the associated codes), which will worsen the fuel economy.
If you have access to the donor car, and you want to use OBD2, install the above mentioned. Im still considering doing the same, just have'nt had the time(M3 cams + M50 intake await install also )
The ews stuff is exactly as the others have noted, and in my case has worked flawlessly for almost 3 years. If you can get a key, buy 2. Cheap insurance in case one shits itself(not unheard of).
The above was info from a factory tech 3 years ago, and proved to be helpful when I did my swap. Biggest problem still seems to be too many opinions from people who have never even attempted this swap, but feel compelled to regurgitate rumours as fact.
Dudes like etasport, stereoinstaller would've been a godsend to me years ago, as they obviously know what they're talking about.

With respect to tuning, take a stroll over to a e36 site. No shortage of people there tuning, many with dyno charts posted.

[WillisE30]

No, I'm pretty sure you can.

If your tuner is good enough with code it is theoretically possible. I can't say if it's ever been done or not.

[PiercedE30]

No, I'm pretty sure you can.

[etxxz]

:no: you can't do the o2 sensors either...he's thinking obdI EWS.

[e304me]

can they disable ews with obd2?

[PiercedE30]

Why not just send off your ECU to have the EWS and rear O2 sensors disbled? It would definitely save you some headache.

[EtaSport]

Fuck!

In theory, if you could determine the hex code of the ISN for the DME you are using, you could generate the signal artificially. However I wouldnt be able to tell you how to do that, or if it would even work.

[EtaSport]

yaaaay im a badass at searching

So its pretty much just like an obd1 swap except for the ews right?

any good wiring diagrams that can be used to figure out the rest of the wiring?

In theory, it seems much easier than converting to obd1, plus it can be used on engines where obd1 is not possible.

It is easier in the way that you already have your sensors and harness, but you have to add a lot more. It does seem to cost a lot to convert to obd1, but for some people it is still the best option. Depending on your emissions laws, some swapped cars require all the emissions equipment that was installed on the engine to still be there. So you'd have to run a secondary air pump, all the convertors, and all 4 o2 sensors. Obviously there are ways around it, and most states do not require this. But obd2 is still designed for 4 o2s which means sims may be required.

For most guys its just easier to do obd1, although i do think the Siemens systems are much better. And nowadays people cant even use the tuning card anymore as there are many tuners of obd2 cars.

[StereoInstaller1]

It is a digital signal via a data line.

Fuck!

[EtaSport]

Right, but what kind of signal goes from the EWS module to the ECU?

The EWS module sends the Individual Serial Number to the DME. The ISN is stored in the DME and the EWS. It is a digital signal via a data line. If the ISN match between the DME and EWS the DME will pulse injectors and fire the coils.

This differs from EWS I because there is no ISN on EWS I. The ISN is used in EWS III (3.2), but a rolling code is added in EWS III (3.3).

[e304me]

yaaaay im a badass at searching

So its pretty much just like an obd1 swap except for the ews right?

any good wiring diagrams that can be used to figure out the rest of the wiring?

In theory, it seems much easier than converting to obd1, plus it can be used on engines where obd1 is not possible.

[SchnellerVert]

http://wp1016621.wp027.webpack.hoste...240/f00240.htm

Info: posted prior to reading complete thread. It's possible as everyone has said.

[StereoInstaller1]

Right, but what kind of signal goes from the EWS module to the ECU?

[EtaSport]

You have to have a valid VIN and registration to be able to get new EWS keys from the dealer. You can order the EWS module (they must be vin specific) and it will get the car started, but after it is installed it must be coded. The only problem is, you wont be able to get a key unless you know the previous owner.

On new cars the keys have the digital passcodes stored in the transponders, and they are initialized by putting them in the ignition on KL15 for 30 seconds. The ews module does the rest. The only reason they are VIN specific is to operate the key tumbler. The key must match the EWS version though as the transponders use a certain AM (i think its AM) signal.

[StereoInstaller1]

Sounds like i'm screwed. I dont have the ECU/antenna/signal booster/key from the original car, as this was a "mail order" motor.

Looks like I'll just have to pony up for the OBD1 stuff!

EWS module and Key need to match, antenna and signal booster can be from any OBDII BMW, AFAIK.

OK, since this link was posted I got the translated page here

This wiring diagram shows 2 wires That I have questions about...What the hell kind of signal does the green wire (pin 18 on the ECU) get? Is it a digital signal, or is it a pulsed analog signal, or what? Obviously, that EWS module puts out something...
Another question I have is can a EWS/key from an earlier BMW be used? Could you grab a EWS and key from a '95 525i to make a OBDII ECU happy?