Values on ECU

Dear Sir. 
I have trouble shooting my 3.0 CSI D -jetronic and find and fixed several of problems. But it still goes rich CO 5.4. Before I started it was 7.9. 
Two things I didn’t figure out is first when I test the coolant sensor on air valve it has correct ohm values cold and hot but when I start the car and measured pin 23 and 11 the tester goes blank until I turned the car of. 
Is it something wrong with the ECU and it won’t get the signal from sensor and think that the car is still cold?
second is it possible to send you the ECU if you can measure it?
Best regards 
John Öijermark 
Sweden 

Dear John,

if you measure with an ohmmeter the correct temperature dependent resistivities at pin 23 of the connector of the ECU (when the connector is unplugged) with respecht to ground (pin 11) everything seems to be o.k.. Then the ECU will get the right input signals.

On the other hand, I do not understand what you mean with "start the car and measured pin 23 and 11 the tester goes blank". What kind of tester do you mean in this case? Hopefully not an ohmmeter.

Best regards,
Recardo

Hi John,

ECU measures temperature resistors via voltage divider. You cannot measure resistors in parallel to ECU, only with disconneted ECU.

If engine temp sensor is correct and MAP sensor is not leaking vacuum and untouched, then only false air or fuel pressure remains to explain such a high CO.

I will now go to vacation so I cannot be of help. Generally ECU should be the last thing to be suspicious about.

Ok.
Thanks for your quick reply.
I measure with the contract in ECU and on pin 23 and 11 with an ohmmeter.
/ John

Thanks for your quick reply.
Ok.
I have been in contact with Bosch classic on color marks on ECU and map sensor.
I have a red spot on ECU and no color mark on map sensor. Numbers are correct but not color marks.
They say it’s not possible anymore to match them and it’s not so important. But I don’t really think that’s the case if I read your website. What do you think about that?
/ JohnThis is the answer and question with Bosch classic 

“Sehr geehrte Damen und Herren,

anbei erhalten Sie eine neue Nachricht der Bosch Technischen Hotline ATR auf Ihre Anfrage: 16844821.       Dear Mr. Öijermark,  During assembly in the BMW plant, the components that matched each other without high tolerances were identified by dots of the same color. After about 45 years this is no longer possible. So that should be fine.Since you can measure the CO content in the exhaust gas, I am sending you the setting instructions for ignition, dwell angle, idling and CO content for your BMW 3.0 CSI in the attachment. Sincerely Bernd Treptow  Hello. I have a working MAP sensor 0280100030 with no color mark and an ECU 0280001007 with a red color mark. Can that combination work? The CO on the car is way to rich 7.8 % and I can’t find any other problems. Best regards John Öijermark Sweden”

Hi John,

of course it is possible to match them. No color does not mean that it is colorless. It could well be that the color spot was removed somehow. That is why my lists also shows the date of make. That allows to verify whether it matches correctly.

Bosch Classic has the ability to make a colorless, blue, red or green MAP sensor. I know how they work and their references include this information. It is more a process issue due to BMWs failure to create a new number. They kept the same number where others used a new one. And that creates all the confusion today. Somewhere I must have the original BMW info that explicitly warns to combine numbers correctly. Now Bosch receives a MAP sensor 0 280 100 030 for repair and that is all they have. What shall the person at the test bench do? Ask someone to identify and contact the end user thus find out the real need? Well that poor guy needs to get its job done. When I go to workshops I often have green, blue and colorless version with me. My advantage is that I know which cars are going to come. And if we see problems we can mostly swap with correct products.

However the difference is in upper part-load and full-load. So it will not influence idle-run CO. Maybe 1 addtl. idea: BMW has one special setup. Cold start valve is used to do after-start enrichment. If something goes wrong here, it might create trouble. I propose that for a test you can close fuel hose to cold-start valve. Most probably it works but it is an addtl. possibility.

Just tell Bosch Classic that Dr-DJet is able to create BMW MAP sensors of every color. I am happy to consult them. I know their names in Nürnberg and I am sure they also know mine. In the end all they need is another tag on their order form for BMW ECU date of make.