Volvo: 1990 740 turbo wont start, sparkplugs, compression test

Question
on my way to work my car died out. it cranks but wont start. a few times it did start but died shortly. in the past i had problems with the car. i had to change all the belts, sparkplugs, starter, haul sensor(?). i dont know what the problem can be. a mechanic came to take a look, but wasnt able to find the problem. he believes its a sensor problem. said something about the pistons not been able to open up? its kinda hard for him to get a real idea, since the volvo doesnt have a cpu harness diagram. any help would be nice.

                                 alex

Answer
Alex,
I would start by checking fuel pressure. If it has none see if the pump or pumps are working. Test for power to them. Pistons only go up and down to create compression, valves open. If they do not open maybe the belt is broken or misaligned. A compression test may also help, first make sure that the engine is in time (all marks on the belt lined up). Sometime the intercooler hoses come loose or rupture and the engine will not start, check those and also see that there is not a breach in the intercooler. Best advice I can give to you seek a shop that knows Volvo for your repairs, they know what to look for and how to repair it in the best way. Their experience means a lot...