I have an '84 EURO spec 635CSi that fails NOX emissions testing. I've replaced all the air-handling and vacuum hoses and tubes, replaced the cat converter, checked for leaks, had the mass air flow sensor checked & "adjusted", and installed a new O2 sensor (the old one had the lead broken off at the sensor). After all this, there was absolutely NO reduction in the NOX emissions. The HC and CO emissions are way low, and the mixture is very lean. I checked the O2 sensor output, and it's STEADY at 0.945 vdc at idle. Looks to me like the ECU is ignoring the O2 sensor.
The (EURO?) ECU is PN 0-261-200-018. Should this pn ECU even use an O2 sensor input? (or maybe the O2 sensor and harness wire was added without being connected when it was brought in to the US)
Is it possible to "plug-in" a US ECU PN 0-261-200-059 to replace the EURO ECU? Or are there way too many differences in measurement and control parameters between the two ECU's? If not, what sort of harness/wiring changes are required?
Does anyone have the I/O connector data for the two ECU's?
I've spent over $500 in "THE" local "qualified" BMW shop, and over $600 in new hoses, sensors, etc, etc, etc, and the NOX emissions have not been reduced. The dealers eyes roll back in "his" head when he hears "EURO spec". The shop even tried connecting up an EGR valve. NO IMPROVEMENT.
The prevailing opinion is that the mixture is way too lean (and combustion way too hot).
If the EURO ECU doesn't use the O2 sensor input, and the US ECU can't be retrofitted to the EURO spec car, has anyone got experience with water/alcohol injection in cars as a means of reducing combustion temps or reducing the residual oxygen in emissions? Any other magic that should help to reduce NOX?
This car's too nice (and quick) to become a "garage queen". Compression is very healthy at 210 psi cold cranking. My '87 635 is only 175 psi.
Any, and all help or suggestions will be appreciated!
Thanks...
The (EURO?) ECU is PN 0-261-200-018. Should this pn ECU even use an O2 sensor input? (or maybe the O2 sensor and harness wire was added without being connected when it was brought in to the US)
Is it possible to "plug-in" a US ECU PN 0-261-200-059 to replace the EURO ECU? Or are there way too many differences in measurement and control parameters between the two ECU's? If not, what sort of harness/wiring changes are required?
Does anyone have the I/O connector data for the two ECU's?
I've spent over $500 in "THE" local "qualified" BMW shop, and over $600 in new hoses, sensors, etc, etc, etc, and the NOX emissions have not been reduced. The dealers eyes roll back in "his" head when he hears "EURO spec". The shop even tried connecting up an EGR valve. NO IMPROVEMENT.
The prevailing opinion is that the mixture is way too lean (and combustion way too hot).
If the EURO ECU doesn't use the O2 sensor input, and the US ECU can't be retrofitted to the EURO spec car, has anyone got experience with water/alcohol injection in cars as a means of reducing combustion temps or reducing the residual oxygen in emissions? Any other magic that should help to reduce NOX?
This car's too nice (and quick) to become a "garage queen". Compression is very healthy at 210 psi cold cranking. My '87 635 is only 175 psi.
Any, and all help or suggestions will be appreciated!
Thanks...
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