The engine cranks but does not start?

2001 MERCURY GRAND MARQUIS
135,000 MILES • 4.6L • V8 • 2WD • AUTOMATIC
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SIXTY6GTO
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Car sat for 2 months. Car will crank but not start. researched a little bit already and tried to do key on and key off 20 times and then car started after possibly building up fuel rail pressure. It could be the drain back of the fuel rail? I think so. Can you tell me if there is an anti-drain back valve in the fuel pump and if so, can I see the diagrams and schematics to find, repair, understand, and replace the faulty parts?
May 22, 2025 at 4:38 PM
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STRAILER
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Does the engine run on starting fluid? If so then I have seen the fuel pumps go out in these cars, yes there is a drain back check valve built into the pump. I would also check the inertia switch reset which is located:

The Inertia Fuel Shutoff (IFS) Switch is located inside the luggage compartment on the left-hand side, on the support.

I would change out the fuel filter as well, this video can help:

https://www.youtube.com/watch?v=wi6kzRjk5to&t

This video will show you how to do the starting fluid and another great tests:

https://www.youtube.com/watch?v=lXLJbuAZ4CE&t

Check out the images (below). Please let us know what happens.
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May 23, 2025 at 11:59 AM
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SIXTY6GTO
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The car started up after about 24 on an off cycles of the key. I was reading that if i did that it would prime the line. This is why I suspect the drain back problem. I never had to try run the car on starting fluid because it started after 20+ key on /off cycles to prime the fuel line. How hard is it to change the fuel pump on this car? Can you show me where it is and the factory procedures to change it?
May 28, 2025 at 1:43 AM
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STRAILER
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You need to drain the tank first because it needs to be removed to change out the fuel pump. Here are two videos that can help, the second is how to remove the tank on a similar car but the procedure is the same.

How to drain the fuel:

https://www.youtube.com/watch?v=Q5MH2gnyFH0

How to remove the tank and pump:

https://www.youtube.com/watch?v=SOmd3BoE4YU

Please go over these guides and get back to us.
May 29, 2025 at 10:16 AM