Poor performance

1999 FORD EXPEDITION
267,000 MILES • 5.4L • V8 • 4WD • AUTOMATIC
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AFERNANDEZ
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  • 2 POSTS
Bought this truck for $2,000.00. Put in a new alternator put in all 8 new spark plugs and now I need to put in all 8 fuel injectors. And I was told that the catalytic converters are also something to be concerned about. Is it worth the fix? I have very low power when I try to accelerate it feels as if I am driving on a flat tire. Once I let off the gas it stops. Then if I just go real light on the gas it will slowly pick up but the speedometer jumps when accelerating. Please help me.
Jul 28, 2019 at 10:57 PM
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SCGRANTURISMO
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  • 4,897 POSTS
Hello,

The first thing I would recommend would be a compression test. Compression tests are the best tests for telling you the health of your engine's internal health. Here is a link for you to go to explaining how to do this:

https://www.2carpros.com/articles/how-to-test-engine-compression

In the diagrams down below I have included the charts for the minimum and maximum acceptable P.S.I. reading in the cylinders, but as a general rule the lowest cylinder must be at least 75% of the highest cylinder for that cylinder to be good. Please get back to us with what you find out.

Thanks,
Alex
2CarPros
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Jul 28, 2019 at 11:34 PM
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AFERNANDEZ
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Okay, thank you!
Jul 29, 2019 at 7:15 AM
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STRAILER
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This guide can help as well:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please let us know what you find. We are interested to see what it is.
Jul 31, 2019 at 12:50 PM