1990 Volvo 740 won't start when warm

volvo
engines
740
starters

#1

This problem is intermittent, never happens when the car is “cold” - it starts right up every morning. When there is a problem this is what happens: I turn the key, you get all the normal lights and sounds: it’ll crank but it won’t “catch” the combustion and resulting roar and running of the engine doesn’t occur. If I give it gas, that doesn’t make a difference. But sometimes, what has worked, is when I turn the key and if it doesn’t immediately catch, I let it go back, then turn the key again, maybe do this 4 or 5 times and each time it begins to catch a little more then finally the engine turns over (I don’t know if that is the right term) and everything is fine. If I try this trick (just turning key briefly, not holding it there) and it doesn’t start to work - if it doesn’t sound like it might almost make it on the first one or two tries - then it never reaches the point where it does “turn over.”

By the way, I think by now you will understand that I am not a car person, but I do appreciate basic scientific principles, so if anyone can provide insight as to what might be happening, I would be quite thankful.

Also, my mechanic is a Volvo master mechanic.


#2

hard to give advice to a Volvo Master Mechanic,espically when he has car in hand,has the mechanic sucessfully determined if this is a fuel or spark situation?

I wonder if the fuel pressure is being maintained while the car sits,or on the other end are we dealing with fuel fouled spark plugs?


#3

yes, he changed all the spark plugs