10046 Tune Up Interval on 850 & 70 Series Cars
Volvo doesn’t quite stretch tune up intervals as far as some manufacturers, but we still feel they may be a bit optimistic in their ignition tune up interval recommendations. We have found that the B5000 family of engines used in the 850 and 70 series like fresh spark plugs, distributor cap and rotor. Once these parts get 15,000 to 20,000 miles on them they can contribute to a reduction of performance and misfires, which will activate the check engine lamp.
The cap and rotor can be replaced in about 15 minutes with common hand tools.The plugs are easily replaced using a 5/8” spark plug socket with rubber retention insert. No need to worry about messing up the firing order as the distributor cap and wires are numbered with the number 1 cylinder beginning at the passenger-side. Have a service manual at hand just in case you find something unusual. A service manual also provides information on how to perform other important tune up and service procedures like replacing your air and fuel filter, and how to flush your transmission fluid.