W124 1987 260E Running Rough
 

All,

Once I get the car running for about 10 seconds, it starts running really rough. I presume it's one of the 3 sensors from back to front of engine block [2-pin sensor, 1-pin sensor and 3-pin sensor]. The 3-pin was recently replaced. Can anyone tell me what these sensors are? The 2-pin and 3-pin come up as coolant temperature sensors when I search for the part. My manual says the 2-pin is associated with the CIS. Any help would be appreciated. I'm almost inclined to replace the 2-pin at the very rear of the engine block to start off with.

Best Regards,

sjsfiji

The sensor at the back of the block is the oolant engine temperature is a 2 pin sensor .Green in colour with 2 push on plugs .This can cause problems .It sends the message to the ecu to set the fuel for the hot or cold mixture .If faulty it can send the info to say its hot , and then ecu will lean out the mixture. Or can work the other way, engine could be cold and the mixture will need to be made rich, but ecu had no mesage to tell it to do so and its keep lean . So worth a change if you can replace it . Tight to remove it ,but it can be done .Have you an economy gauge on the console? If so is it on the far left at start up?

Thanks
 

Thanks optimusprime.... Sensor is on the way...

Now this is not a 100% get you out of jail information i gave to you . But can be a source of the problem . I have just replaced mine thats how i know about them .We will see, after you install the sensor .