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running rich? lots of black smoke 700 1989

posted by  someone claiming to be Stephan Brendler on  Wed May 30 22:41 CST 2001 [RELATED]

1989 744gl; B230F; LH 2.4

I installed a new ECU-temperature sensor and a new throttle body gasket. Before my brick runs very rich (temp-sensor to high resistance). After this job the smell isn't as bad as before but lots of black smoke come out. What happens? Basic maintenance is done (filters, plugs, connectors checked).

I checked for errorcodes but only this knock-related error 312 is present (this week i get the new knock sensor). Whats about the lambda sond?

Please help me making my brick running better! Thanks a lot!







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    Re: running rich? lots of black smoke 700 1989

    posted by  someone claiming to be JohnB on  Fri Jun 1 06:38 CST 2001 [RELATED]

    try disconnecting the AMM (engine off). This sends the system into limp home mode, reduced power because the ecu gives fuel based on engine rpm only, will/should act lean.

    It's possible the air mass meter is overfueling the engine?







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    Re: running rich? lots of black smoke 700 1989

    posted by  someone claiming to be Haroon on  Thu May 31 06:16 CST 2001 [RELATED]

    You might as well check the o2 sensor. Easy to do.







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    Re: running rich? lots of black smoke 700 1989

    posted by  someone claiming to be Steve Ringlee on  Thu May 31 01:09 CST 2001 [RELATED]

    Another cause could be your fuel pressure regulator. If it malfunctions, it typically allows the engine to run very rich. Pull off the vacuum hose and see if petrol is present, the sign of a leaking diaphragm.







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      Re: running rich? lots of black smoke 700 1989

      posted by  someone claiming to be Graham Carter on  Thu May 31 09:12 CST 2001 [RELATED]

      If your getting crap mpg and all else seems ok then new pressure regulator.

      From about 12 mpg back to around 20 mpg when I did mine.







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        Re: running rich? lots of black smoke 700 1989

        posted by  someone claiming to be Stephan Brendler on  Thu May 31 09:39 CST 2001 [RELATED]

        Fuel pressure regulator seems ok (no fuel in vacuum hose). Try checking lambda sond tomorrow. Thanks for your input. If anyone has further ideas - let me know.






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