by Lincoln Crawley
(Gold Coast Australia)
Port engine was going into limp more intermittently following a few seconds of rough idle. Revs go to 1000 and neutral is engaged. Diagnostic button returns 2.7 which is potentiometer out of ohms range. Some days it would happen a dozen times, other days it might happen only once. Have swapped potentiometers and ECUs but the problem stayed with the Port engine. Eventually found some dodgy looking wire in the short loom under the dash. This was replaced and the problem resolved for a few weeks. We then had a "sparky" dead short the house and starter banks while installing new batteries (didn't isolate!) And since we had been getting strange shutdowns and limp modes, high temp/zero oil pressure reading on guages when temp and oil we're fine. The new tech traced the fault to the black box which was installed in the "engaging forward gear shift from neutral by itself" Volvo recall some years back. So this box has now been removed and we are waiting on a replacement. However Volvo are experiencing big shortages with electronic components due to Covid with not ETA so we have to run the engines without the recall black box for now. My question is this. How often did these engines shift into gear themselves from neutral? Was it rare or should I expect it to happen every time I go out? Does it stay at idle revs or increase revs? Just want to be prepared with my finger hovering on the stop button just in case! Thanks! Lincoln