trouble with gas to the engine
we have replaced the fuel filter and fule pump. We hear the pump running so we know it works. Start driving and a few miles down the road the car stalls like it has run out of gas. We can restart, hear the fule pump come on, drive a few miles and again the same thing.
Check/Replace all fuel filters and check the fuel pressure (after a couple of minutes after startup). You may have a bad fuel pressure regulator or faulty injector.
First, fuel pump relay failure cab be intermittant. it's worth replacing in situaytions like this. It can fail as it "heat's up" or when you hit a bump. The cause is usually a failure of a solder joint internally due to vibration. You can usually get one for between 10 to 20 bucks. Second, your model may have one or two pumps, If two, one may be failing. I've seen symptoms like this on a two pump wagon. Replacing a pump can be a job, but there are directions online. The risk is if it's the in-tank pump. AVOID OPEN FLAMES or SPARKS... You would need a soldering iron. I'd suggest getting help. Lastly If your pups are working then it could also be the fuel preassure regulator. The Volvo 740's need a constant 300 kpa of preasure, but I know of no easy way to test the preasure. The regulator is usually around 50 to 70 bucks.
Search Volvo 740 Questions
Volvo 740 Experts