The idle speed on my 380sl was surging between 1000 and 1500 rpm's a few weeks ago, so I replaced my ICU with a rebuilt Programma, which solved that problem.
However, now, when I start my car, it idles between 600 and 700 in park, and it stays there in drive. But when the temp hits about 60 degrees C, the idle increases to app. 900 in P (750 in D), and it soon creeps up to app. 1000 in P, particularly after driving for a while. However, if I let the car sit for a short period, and restart it, the idle will again be around 700 in P, and it will stay there for a short time until it heats up.
I sprayed brake cleaner on the injectors and every place else on several occasions, but the idle never changed. OTOH, when I disconnected and grounded the O2 sensor, the idle decreased immediately, which leads me to believe that the sensor caused the idle to increase as it heated up.
As most of you already know, the O2 sensor is only about $20, though replacing it can be a PITA. However, before I do, I was wondering if my conclusion is justified.
11-13-2012, 07:13 AM
Linear Mode
