engine shakes badly?

1996 FORD F-150
190,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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FORDSMB454
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when i rev the motor the engine shakes badly i don't know what's going on.

Things I've changed/fixed.


Fuel pump : New
Fuel injectors : cleand not new
O2 Sensors : OLD
Engine mounts : New and Torqd
Vacuum Hoses : All checked no cracks or leaks that i can see
Fuel : New NOT old
Fuel Regulator : New
Fuel Pressure : 35 psi was 15 replaced fuel pump with New one
Gaskets : all new intake/lower intake/heads/exhaust so on

i did Lap the valves and check for leaks with water and a oil test No Leaks i have NOT checked compression yet after new fuel pump i could check that any help would be amazing thank you. also here is a video to show.
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Nov 4, 2024 at 10:27 AM
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STRAILER
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Thanks for the video, it helps. here is a guide to help with the compression test because it looks like you may have a burnt exhaust valve which the test will show.

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

Also, I would check the EGR valve to make sure it is not leaking or getting held open by vacuum which you can check by simply removing the vacuum line at idle. Here is an additional guide to help and I have included a video on how to check the EGR valve for internal leakage.

https://www.2carpros.com/articles/repairing-engine-rough-idle-issues

And the EGR valve test.

https://www.youtube.com/watch?v=DqUCbbKdWf4&t=12s

Here is the location of the EGR valve for your truck, check out the images (below). Please let us know what happens.
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Nov 4, 2024 at 1:23 PM
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FORDSMB454
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the EGR is brand new, and all the valves are lapd and polished all clean and i tested them for leaks no leaks is it possible that the EGR could just be faulty in general even if new? or maybe other issues? that motor is different than mine i have a 96 ford f150 5.0 v8 302.
Nov 4, 2024 at 2:57 PM
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STRAILER
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Okay, I would remove the vacuum line for the EGR to see if the idle gets better. It seems like it would be a vacuum leak, can you spray carb cleaner to see if it will run better? Please go over this guide:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

It could be a spark plug gap, or a bad fuel injector. Can you run the codes to see if any are stored?

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

I have seen the MAF sensor cause this problem as well, I would make sure there are no leak between the MAF and the throttle body. Please go over these guides and get back to us.
Nov 5, 2024 at 9:48 AM