Poor performance

AFERNANDEZ

MEMBER
1999 FORD EXPEDITION
5.4L
V8
4WD
AUTOMATIC
267,000 MILES

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.

3 Replies

SCGRANTURISMO

MECHANIC
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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