1223 error code

[Klonsk8]

nice i will look at this tonight, i drive a 1991 325i .

[DarkWing6]

Jordan is right. I had this problem with my car. You will see a black connector that connects 2 of your main wiring harnesses located about 6-8in below the throttle body and intake manifold. Take it apart, inspect and clean/fix it as Jordan explained. You will also want to replace the cork gasket on the throttle body where the coolant goes in. This $.10 gasket is probably the cause of your problem.

[Jordan]

Yeah, you will need to actually do some work. You did not state what year car you have but since you said the sensor leads go into the fuel rail wire loom I assume its a late model.

As such.. you have a connector under the intake manifold for the fuel rail harness. This connector is very susceptible to water gathering in it and corroding the connections. You need to get to it, pull the connector apart, boots back, etc and I bet that is where you will find your problem.

[Klonsk8]

I only see like 10 cm of the cts wire, after what it goes through the fuel rail.

[Jordan]

Visually check every inch of the wire from the Coolant Temp Sensor to the ECU connector. Chances are one of the wires at the sensor connector is broken or corroded, if not somewhere down the line.

Haywire idle is likely caused by a faulty Idle Control Valve.

[Klonsk8]

Since a week my car have some trouble and its very on and off. Sometimes the car is rough to start. After that, at idle the rpm go like it was possessed. I can go randomly from 750 to 1000 down to 500 up to 2000 down to 1500 up to 2000 and down to 500. I notice lots of mis fire when i drive it. When a pull it hard the car looks fine. But when i'm at redlight the possessed idle comes back and sometimes the car died and its very hard to start it again.

I've read a 1223 error code only from the CPU. So i've changed the CTS, i was ok for 1 day, and looks like the problem come back again. I've ordered a set of ignition wire too, i will probably receive them next week.

Some one have an idea where to look now ?