Flashing MIL, and no lambda control

[Tzl]

Hi guys,
I had to repleace the ECU in my 325i, because it doesn't control normally the idle speed. The old one is a motronic 1.1, and I bought a 1.3, because I read they are compatible, and the 1.3 is a more advenced technics. It is true, engine is running fine and my idle speed became perfect, It is constant at every temperature, but my MIL lamp is flashing very quickly, (not the CHECK signal) and the ECU doesn't adjust the mixture from the lambda probe. It driving the engine with poor mixture, so the car is weaker a little.
But the ECU doesn't store any fault.

The old one is controlled it, because a few month ago my car was on a CO check in a garage, and there the guys show me that the lambda control is working.

I already checked the lamdba probe. I manually moved the shaft of the air flow meter a little clockwise and opposite direction, and the lamdba showed when rich, and when poor the mixture (0,1V and 0,8V), but the ECU didn't respond, and didn't adjust the injected quantity. And also the MIL was flashing continuously.

When I know in two cases don't control the ECU the lambda, if the engine is cold, or/and the wide throttle switch is signaling. But both condition is works.
Is there any condition of the lambda control?
I think the new ECU is faulty.

Everyone has any idea?
And what is meaning the flashing MIL lamp without fault code? The two thinks is related?

Thanks:
Tzl

[Speedtouch]

Hi, I notice you have an '87 325i with 0 261 200 153 ECU originally. It would help if you tell us which ECU number you have swapped to, e.g., 0 261 200 173.

Usually, you can't directly swap M1.1 for M1.3, since the ECU pinouts are different - either the ECU plug and socket won't fit, or it won't run at all!

[Tzl]

Hi, I notice you have an '87 325i with 0 261 200 153 ECU originally. It would help if you tell us which ECU number you have swapped to, e.g., 0 261 200 173.

Usually, you can't directly swap M1.1 for M1.3, since the ECU pinouts are different - either the ECU plug and socket won't fit, or it won't run at all!

Hi,

Yes, you're right: 153->173

When I remebmer, the 1.0 ECU has different socket, -pinout, and -engine loom.

In my case, the sockets are same. I just plugd the new ECU, and the engine started first. And all function is working, except the lambda.
In the pinout table I found only two extra pin at the 1.3, these wires go to the ABS, called fuel cut-off, but these wires I didn't see any electric drawing, what I found on the net. So I don't know what are the functions of these wire.

Therefore I'm confused, because about my informations this swap has to work. But if you have any new information please help.

Thanks:
Tzl

[Speedtouch]

This article might help with your problem:

https://www.bimmerforums.com/forum/show ... -1-1-3-BMW

[Tzl]

This article might help with your problem:

https://www.bimmerforums.com/forum/show ... -1-1-3-BMW

Thank you!
I know this artcile, I reed it several times.
But I think he was wrong about the different power supply of the 1.1 and 1.3. When I looked over the electric drawings from '86 to '91, what he writes is about the differences beetwen the 1.0 and the 1.1/1.3. According to the drawing there is no difference the 1.1 and 1.3.
But it does not matter, beacuse I found some misprint earlier in the drawings, se when I have time, I will measure the full power supply of the ECU.

In the meantime I noticed, the frequence of the MIL flashing is depends of the engine speed. At higher speed the flashing is a little slower.
I thing this flashing is a for a moment appearing fault, what is comming back cyclically. But maybe not enough long for storing the fault code. But this is just a supposition.

I will search somebody, who has diagnostic tool for these old cars, and maybe in the live data I can see more.

Thanks again:
Tzl