Your welcome. …
I have so far still been unable to measure the centering of the AFM plate ... ... Just eyeballing it, it does not look off center to me ...
Sounds good enough to me.
... however it does appear to rest slightly higher than the cylindrical portion of the AFM (rests just at the bottom of the tapered part) ...
It should be as described under step 5 of the PDF-file I attached in post 39.
... If I am only able to come up with one analog voltmeter, which should I use the analog meter on? ...
That depends on the meter‘s measuring scale … with 0-1 volt, I‘d use it for the o2 sensor voltage … with 0-20 volts, I‘d use it for the duty cycle (if I had no duty cycle meter). … The meters do not have to be analog, however, with analog meters fluctuating readings are a lot more comfortable to monitor than with digital meters.
... How can I simultaneously measure system and lower chamber pressures, do I simply need 2 fuel pressure meters? ...
Yes. … But if you don‘t have two manometers, one is also okay. In that case measure ‘System Pressure‘ at idle speed and at higher revs first. It should be the same at any rev ! … Then, in the video, measure the much more interesting ‘Lower Chamber Pressure‘.
... Just to make sure I do this right the first time, would you mind creating a diagram of how to connect the EHA? ...
See attached diagram. … With the key turned to “ignition on“ (engine not running) on a M103 the ammeter should read +20 mA
! … If you see a negative value, change the polarity of the measuring cables !
... What range should I be looking for in the voltmeter and ammeter? ...
The expected maximum measuring ranges for the described tests on your car are:
- o2 sensor voltage: 0-1 V
- duty cycle: 0-100 %, respectively 0-15 V
- EHA current: 0 +/- 10 mA (+20 mA with ignition on, engine off)
- fuel pressure: 0-5.5 bar (80 psi)
... In regards to your email issue, I'm recieving email notifications so maybe the problem is on your end? ...
I‘m only receiving notifications about PM‘s, however, with a day or two delay. … In case of new posts in threads I‘m subscribed to, I haven‘t received any notifications for a week now … also not about this post of yours. …
... Additionally, my cars performacne and reliability has been sharply declining lately and I fear my spark plugs may need to be changed/ cleaned soon. Will this nullify any of the tests we have done so far?
As I said in my Lambda control thread, “Generally problems relevant for the fuel combustion have an influence on the EHA control, hence on the duty cycle.”
. … And fouled spark plugs, of course, are a problem relevant for the fuel combustion … affecting o2 sensor voltage, thus the ECU‘s reaction (EHA current & duty cycle). … It‘s definitely recommendable to do the tests with good spark plugs !
The closed-loop o2 sensor voltage test (test 1 from post 37) will be part of the simultaneous tests (post 45) … but I also suggest to repeat the open-loop o2 sensor voltage tests (tests 2 - 5 from post 37) with new spark plugs.
And I suggest to complete the simultaneous tests (video) like this:
While the engine is running at idle speed move the AFM plate manually
slightly up and down … (a magnet would facilitate moving it up). Keep the plate several times in both positions (the slightly risen one and the slightly pushed down one) for about 2 seconds each. Keep it as far up and down as possible without stalling the engine (which can easily happen!). Do that, like the other simultaneous tests, with the EHA plug connected
and with the EHA unplugged