D-Jetronic Problem!!!!!

Hi,

in which range can you adjust CO if you leave air temp sensor on connector?

Thanks for your prompt reply! Below are the data of the CO with air temp senor plugged in to the connector.

Under engine's operating temperature 80~85 degree celsius & there are total 20 clicks at the knob of ECU from the left (the leanest) to the right (the richest):

The 20th click (the richest and to the far right): CO 0.8~0.9% during idling
The 10th click: CO 0.16~0.20% during idling (the engine starts to die during deceleration at this and below clicks)
The 1th click ( the leanest and to the far left): CO 0.15%

The ignition timing 0 degree to 5 degree BTDC
The MAP vacuum leakage is perfect (~0.5-0.49 bar for more than 10 sec.)
The idling RPM is 720~800 with a little bit hesitation, and the exhaust is not continuous with intermittent popping sounds

Hope these reference points are helpful!

Hi,

can you tell me hiw your CO is when you disconnect throttle switch?

All this sounds strange as if tuning of MAP sensor was wrong. If it was not repaired by Bosch itself I would claim that it was done wrongly.

Thanks for your instruction! Below are the performance data of the car:
When engine operating temperature reached 82~85 degree celsius & disconnect wires connector on throttle switch, then start and running engine at RPM 850~900 with CO 2.7% (0.55 bar vacuum during idling)

After 2 mins of running, RPM 730~820 with CO 0.19~0.20%
After 5 mins of running, RPM 730~820 with CO 0.17~0.18%
After 10 mins of running, RPM 730~820 with CO 0.17~0.18%
After 15 mins of running, RPM 730~820 with CO 0.17~0.18%
There is no change since then, so I turned off engine

Regarding the suspicion of the faulty MAP sensor, I hope it is not the case, cause it is not about the price, but it is too troublesome to communicate with BOSH service center for rechecking and retuning, as they have not replied me yet.
May I humbly ask if you would recommend me to return the MAP senor to BOSH for rechecking and retuning or buy a new/rebuilt MAP sensor? Thanks~

Hi Danny,

as you tested all sensors okay and a vacuum leak would rather create higher than lower CO I am a bit puzzled. Normally I would now be supsicious about MAP sensor and maybe ECU. But as it was tested okay by Bosch, I have to think of other possibilities why your car would run so lean.

Fuel pressure and injectors are okay?

Thanks for your prompt reply! Below are the data regarding fuel pressure and injector:
Fuel pump's parts number: 0580464042
Fuel pump connector with 12.6 V when engine idling
I use battery to power 12V to fuel pump (it released 1.5L fuel in 30 sec.)
Fuel system pressure 1.9~1.95 bar when engine idling
after ignition off 5 mins: 1.7bar system fuel pressure
after 10 mins :1.5bar system fuel pressure
after 15 mins: 1.2bar system fuel pressure
After 20 mins: 1.0bar system fuel pressure
After 25 mins: 0.8bar system fuel pressure
After 30 mins: 0.5 bar system fuel pressure

I just received the ALLSUN EM276 injector tester that I purchased earlier, and I am planning to take out all injectors to check the spraying pattern of each injector. However, there are 4 modes for me to choose for checking injector:
1) output 1 pulse, whose pulse width is about 250ms
2) output 50 pulses, every pulse's pulse width is about 7ms
3) output 100 pulses, every pulse's pulse width is about 3.5ms
4) output pulses continuously at the rate of 50 pulses per about 1450ms, every pulse's pulse width is about 7ms

May I know which mode would be the most accurate and secure for the injector checking? Anything I should be aware of? Thanks again~