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Q: Replaced alternator new, replaced fuel pump new, filter new, relay and regulator and it still will not start? Why?

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Replace Fuel Pump, after new alternator and fuel relay and regulator and sending unit , and checked wirering and it still will not start. will start with spary

My car has 200000 miles.
My car has an automatic transmission.

If the car starts when you use a starting fluid as you say, then it’s clear your engine is not getting fuel. Fuel pressure is of course important, and is easy to test with the right equipment. I Know you have already replaced the fuel pump, but you still need to verify the pressure. The old 740’s depend on air entering the engine being measured by an air flow meter to determine injection quantity. Any air leaks in the intake will prevent the system from delivering sufficient fuel. So check the intake manifold and all the air hoses for anything that is damaged or not fitting well. Starting enrichment may be provided by a cold start valve, inconveniently located under the intake manifold, though that part was deleted right about the time your car was built, so it might not have one. If it does, it is controlled by a thermo-time switch at the top of the cylinder head (colored brown). If you get tired of trying to sort this out, you can contact Your Mechanic. They can send a technician to your home or office to check out your stubborn Volvo and let you know what can be done for it.

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