Volvo Repair: 2001 V70 T-5 Performance Reduced message, sophisticated computer system, diagnostic computer

Question
James, I'm having a situation where our 2001 V70 T-5 occasionally gives a message that says something to the affect of "Performance Reduced" while driving.  Occasionaly the car will die as the idle becomes very erradic.  I've taken it to my repair person who ran codes and said that they were not conclusive, but sugessted that I should replace the throttle body.  He also suggested that a simple software update might fix the problem.  I believe that my wife uses 87 octane fuel.  Any ideas?  Does this sound like a throttle body?  Oh, by the way, the last time this happened the message said to have it serviced immediately.  This was when the mechanic read the codes and said that they were inconclusive.  Thanks

Answer
First, I'm sorry for the delay getting to your question.  I have been in orlando for the past few days for XC90 V8 training and have been unable to take emails.

Performance reduced is the message you get when engine output is reduced because of a misfire.  It will only be on for the period that is is adapting timing and fuel trim to compensate for it.  A throttle body will most likely not fix the problem.  Take the car specifically to the dealership because that car has a sophisticated computer system that isn't able to be serviced entirely with generic diagnostic computer.  The volvo diagnostic computer would be able to have a more detailed description of your problem plus troubleshooting procedures for every code so they WILL be able to find the problem.  Higher octane fuel may help but that may not be the root of your problem.  There are 2 type of service messages.  Time for regular service - which just means that the counter in the computer has reached the number where it reminds you to take your car in for service (oil change, etc.). Not a big deal.  If there is any other message it would tell you what needs repair (transmission service urgent, emmission system service required, etc.). Hope that helps.

James