Just landed from Heathrow carrying a complete Csi system. I
thank you for your detail input , Sunday I will do , and let you know if I find the solutionI defer to the experts, and hopefully you can get your car to sfdon soon.
In the meantime, there are only a couple of inputs to a D-Jet system:
Make sure your vacuum line and electrical connector to the MAP sensor are in place. (see attached pdf)
There are only three other inputs for the D-Jet: Air temp and water temp sensors affect the operation, the throttle valve switch affects injector timing(?).
I once had the experience on my '72 MBZ V-8 with D-Jet that the air temp sensor on the air intake was not seated properly after a filter check. Man, my engine went wild, just a you describe: black smoke, barely running, misfiring, etc. I re-traced my steps, found the badly seated connector, and that was it, purring like a kitten.
On the #9, I believe the air temp sensor is the sensor to the right of the throttle body. The throttle valve switch is to the left.
View attachment 134304
The water temp sensor is under the fuel pressure regulator on the intake side. This affects the cold start circuit:
View attachment 134305
The knob on the ECU unit controls the fine-tune for the CO level after you set the idle with the idle screw on the throttle body. Someone with an exhaust tester can help you get that dialed back in. An expert could probably dial the knob in by measuring the resistance across the potentiometer (the knob's function), but I don't know what a nominal value should be.
Hopefully just a dislodged connector, and not the end of the world! Good luck!
Thank you , I am checking to see if this is the problem ,,,, you are a big help , Thank you for your timeI have had once rpm jumping up and down in BMW with BOSCH Motronic ... after I have checked almost all including vacuum, fuel pump, charcoal, MAF I noticed there is one more part in the injection system ... fuel pressure regulator.
It's dry side is driven by small pipe with vacuum from intake manifold. Once I slipped the vacuum pipe I notice gas/fuel coming from the regulator.
Green and Eco fuel with ethanol made the diaphragm brittle. It cracked and caused small fuel delivery to vacuum system thus intake. ECU was trying to stabilize the rpms but was not able to.
It looks like CSi has nut operated regulator
View attachment 134680
If the pressure is incorrect the whole system will not work properly but to be honest it is probably someting different.
Adjustments
Pressure regulator Remove hose at pressure regulator and connect pressure gauge to regulator. Operate fuel pump. Pressure should be 28 psi (2.0 kg/cm2 ). Loosen lock nut on regulator and adjust as necessary. Replace regulator if specifications can not be achieved.
Source (also some more about idling):