Hello,
I've have a problem similar to other I've found in former posts about engine throtling up and down and finally staying up 4500 rpm with my volvo 460 glt 1.800i. It seemed to be a problem with idling motor, the first time it solved changing idling motor, but two years later it failed again and the ECU was affected too. Now I must throttle after startup during a while until car warms. Volvo mechanic told me that it was caused by alternator sending high current, I changed alternator but not the ECU cause is a expensive part. I've found two second hand ECU from other 460 1800i of the same year, but the part number isn't the same. My car has a ECU Siemens Fenix 3B Spi S101-705-112D, and I've found similar codes that I've found valid in
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codes are S101-705-111 and S101-705-113C. Does anybody know If this ECUs are similar enough to replace my damaged ECU, or some place where I can submit me question?