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Matt, Engineer
Category: Car
Satisfied Customers: 20383
Experience:  Honors degree in Mechanical Engineering, worked 8 years as a Formula 1 engine engineer.
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engine is skiping and back firing and wont stay running

This answer was rated:

engine is skiping and back firing and wont stay running

can you tell me what make, model engine size and how many miles are on the car?
Customer: replied 3 years ago.

1992 F150 5.0 with 138,00 miles


This could be a lack of fuel pressure from the electrical pump at the tank.

If the connections to this are corroded or damaged then the pump could stop at any time or could not be running at full speed. Check that its relay switches in and out and the relay contacts are clean and bright – replace the relay if in any doubt and do the same for the fuse,
Ideally measure the pressure at the injectors and if this is low check the pump as described and also consider changing the fuel filter as if this partially blocked this too will reduce pressure.
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