Secondary air pump simulator installation help w schematic

[rkstar9]

Hi I'm attempting to Install SAP sim for 03 bmw z4(sorry if it's the wrong forum but z4 people don't seem to know about this) and thank you for your patience as I have been struggling w these for the last 6 hours.

I'm trying to figure out which cable to tap into from this schematic and I am having the following issues:


1. o2 sensor to dme upstream cables:
There appears to be only one cable from DME to o2 switch. Shouldn't there be 2 for a 6 cylinder?

2. DME to SAP cable:
there is no cable going from the DME to the sap? instead it apears it's controled by some other module?


3. which ground cable should I use?




also here is the diagram for the o2 system
notice cable 6 from x8680 does not come from the DME but some sort of fuse thing and why is there only one upstream cable?



Also I am hoping to find all 6 wires at the DME so I can place the simulator there but it looks some of the cables get under the driver and passenger side?

Thanks in advance

[xxxJohnBoyxxx]

Originally Posted by rkstar9

Hi I'm attempting to Install SAP sim for 03 bmw z4(sorry if it's the wrong forum but z4 people don't seem to know about this) and thank you for your patience as I have been struggling w these for the last 6 hours.

I'm trying to figure out which cable to tap into from this schematic and I am having the following issues:


1. o2 sensor to dme upstream cables: There are two O2 sensors on a I-6 motor, Each O2 needs to be spliced into the simulator
There appears to be only one cable from DME to o2 switch. Shouldn't there be 2 for a 6 cylinder?

2. DME to SAP cable:
there is no cable going from the DME to the sap? Again you only use on wire from the O2 which is the signal wire. That wire is cut and the simulator is patched into the O2 signal wire that you cut.instead it apears it's controled by some other module?


3. which ground cable should I use? Body ground is good since that is what the Air Pump uses anyways




also here is the diagram for the o2 system
notice cable 6 from x8680 does not come from the DME but some sort of fuse thing and why is there only one upstream cable?



Also I am hoping to find all 6 wires at the DME so I can place the simulator there but it looks some of the cables get under the driver and passenger side?

Thanks in advance

Bold answers in the quote

[rkstar9]

Originally Posted by xxxJohnBoyxxx

Bold answers in the quote

Thank you

Any pointers on how to identify the o2 upstream cables since each sensor has 2?


also for the + SAP feed. it seems the dme shoots a low voltage wire to a relay that in turn powers up the SAP w more voltage

would you suggest to tap that signal right at the dme before the relay or after ?
and can I just tap into it without cutting it?

[xxxJohnBoyxxx]

Originally Posted by rkstar9

Thank you

Any pointers on how to identify the o2 upstream cables since each sensor has 2? Yje O2 should have 4 wires two the same color which are the O2 heater and 1 ground. The remaining wire is signal and is the wire you cut and patch the sim into.


also for the + SAP feed. it seems the dme shoots a low voltage wire to a relay that in turn powers up the SAP w more voltage

would you suggest to tap that signal right at the dme before the relay or after ?. Do not tap into the DME for positive it could burn it out. You need to tap into the original positive wire for the air pumpand can I just tap into it without cutting it?

In bold

[rkstar9]

I did everything as instructed took my time to make sure I didn't cut the wrong cables. I reset the check engine light and drove 50 miles so far in freezing weather making sure to drive hard on start up. Seems to have worked fine!



I must say from doing a lot of research every other bmw forum pretty much points back to your thread. so thank you for pioneering this project and for your real time on demand support!

I will be sure to create a tutorial for the z4 community so that all other owners with newer cars who will potentially have this issue can sort this out faster.

[xxxJohnBoyxxx]

Originally Posted by rkstar9

I did everything as instructed took my time to make sure I didn't cut the wrong cables. I reset the check engine light and drove 50 miles so far in freezing weather making sure to drive hard on start up. Seems to have worked fine!



I must say from doing a lot of research every other bmw forum pretty much points back to your thread. so thank you for pioneering this project and for your real time on demand support!

I will be sure to create a tutorial for the z4 community so that all other owners with newer cars who will potentially have this issue can sort this out faster.

Thanks for the comments. Glad the project helped you out. John S

[KPATX]

I built a SAP sim according to this schematic http://www.318ti.org/forum/showpost....9&postcount=25 except that I wired the pot with the wiper arm (middle wire) as the 200 mV source. The schematic did not make sense to me otherwise with the pot as a voltage divider.
According to my Haynes manual, the forward o2 sensor wire connectors hook into the wires to the dme along side the fuel rails. The wire colors are red, yellow, black, and white. Readings there with a Fluke 77 dvm referenced to the chassis ground nut by the SAP were unstable, so I used the ground side of the SAP connector. The yellow wire was the one that varied between 0-1v., gradually increasing as the engine warmed up.
Can anyone with a '96 328i verify that this is the correct wire? I ask because after resetting CEL it came back a couple of times, though it didn't this morning. Wife left in it this morning and it was running fine but can't tell yet because we're still having problems with a P0340 CPS error and I can't check 'til she gets back.

[xxxJohnBoyxxx]

Originally Posted by KPATX

I built a SAP sim according to this schematic http://www.318ti.org/forum/showpost....9&postcount=25 except that I wired the pot with the wiper arm (middle wire) as the 200 mV source. The schematic did not make sense to me otherwise with the pot as a voltage divider.
According to my Haynes manual, the forward o2 sensor wire connectors hook into the wires to the dme along side the fuel rails. The wire colors are red, yellow, black, and white. Readings there with a Fluke 77 dvm referenced to the chassis ground nut by the SAP were unstable, so I used the ground side of the SAP connector. The yellow wire was the one that varied between 0-1v., gradually increasing as the engine warmed up.
Can anyone with a '96 328i verify that this is the correct wire? I ask because after resetting CEL it came back a couple of times, though it didn't this morning. Wife left in it this morning and it was running fine but can't tell yet because we're still having problems with a P0430 CPS error and I can't check 'til she gets back.

Sorry but the schamatic you used is not mine. It is someone elses and I don't know anything about it. You need a 2-bank and fool both upstream O2's fooling the computer into thinking it has extra air in the exhaust from the air pump. My connection is signal wire cut only and patch the simulator into the signal wire only.

[KPATX]

Originally Posted by xxxJohnBoyxxx

Sorry but the schamatic you used is not mine. It is someone elses and I don't know anything about it. You need a 2-bank and fool both upstream O2's fooling the computer into thinking it has extra air in the exhaust from the air pump. My connection is signal wire cut only and patch the simulator into the signal wire only.

I understand. It is a two bank simulator with both wires cut and passed through with a common 200mV source into both wires to the the dme while activated.

[KPATX]

Originally Posted by xxxJohnBoyxxx

Sorry but the schamatic you used is not mine. It is someone elses and I don't know anything about it. You need a 2-bank and fool both upstream O2's fooling the computer into thinking it has extra air in the exhaust from the air pump. My connection is signal wire cut only and patch the simulator into the signal wire only.

The schematic is functionally the same, but uses a single dpdt relay instead of two spdt relays and a single pot instead of two. It supplies exactly the same voltage to both of the dme inputs instead of a possible deviation when used with two pots as in your schematic.

I was essentially asking if anyone was familiar with the o2 signal wire color on a
'96 328i.

No SAP code again this morning (1-1-13). So it was the YELLOW wire that was o2 signal FYI.