Hi My Engine Light came on and i read the ECU Code and it reads "Closed Loop Control"

What is the Problem, what causes it, and How do i fix it?

Thanx.

Please, Anyone with a similar problem or know whats the problem please help.

Steven

 

i had same code along with knock sensor and 02 sensor, they ended up changing the 02's and crank sensor saying the other things were not needed, im also interested in knowing what this does

 

IIRC I had (or maybe have still) this code. It makes the car run in open loop (aka WOT fuel and spark maps) all the time. Might waste a little fuel but once you punch it nothing's affected, just may run a little rich while at partial throttle.

Causes could probably be any combination of sensors, including o2, etc.

 

Reset the ECU and watch for another code to pop up. Something isn't allowing the ECU to run in open loop mode. When it finally figures out which sensor has gone bad, it will throw that code along with your closed loop control code.

My thoughts are that the Emgine Coolant Temp sensor may never be reporting to the ECU that your engine is up to operating temp, giving it the OK to run in open loop mode. If that sensor goes out of calibration, but still sends a signal, the ECU see's it as a working device. Try to clean the contacts on that sensor, I've seen a few of them look pretty bad. A bad connection could throw the readings off. The Haynes manual has the specs for that sensors readings at various temperatures. You can easily check the ECTS with an ohm meter.