It may be rust or just that the engine is old
In response that the car wont start due to it being old: I have worked on Volvos many years and own three of them now, 2 are 850 s and being old doesn't keep mine from starting. When a car won't start think fuel, fire and air. All 3 are needed for the car to start. See if the engine is firing if not could be many things but on 850s the coil is the first thing that comes to mind. If you are getting fire (the spark plugs are firing) then check the fuel. If no fuel then can be filter or fuel pump bad. Hope this helps and good luck.
the battery my have a bad cell, or the starter may need to be replaced
it does
Check condition of ignition coil. Replace if bad.
take distributor cap off and see if rotor button is turning when crank over
The 2005 comes with a five digit (all numbers) code. After the battery is replaced, turn on the radio. The radio should show "Code." Simply punch in the five numbers on the turning buttons and the radio will immediately start working.
it may be 180 degrees out try turning it 180 try resetting your timing it may be too far out to allow it to start
It is zeroed to the crank with a scan tool. It can not be done with a timing light. It is done by turning the distributor.
You can monitor distributor degrees with a timing light.
i have the same problem on a 91 dodge and i took distributor out and pulled the gear out and it was striped u can see cam turning but not the distributor so check and see if its turning
try turning it off then removing the battery then putting the battery back in the turning it on. it worked on mine
Check the main relay under the dashboard the fuel filtr and distributer.AnswerCheck the distributor cap, rotor, and spark plug wires. With the distributor cap removed, crank the engine to see if the distributor is turning if not you probably have a broken timing belt.
The way the rotor rotates retards. If the distributor turns clockwise, then turning the distributor clockwise retards the timing.