5.4 Sluggish No Codes
Junior Member
Joined: Aug 2024
Posts: 1
Likes: 0
Just fixed this same problem
Hi all
To start, my truck 2004 5.4, over the past few months has begun to stutter under loads. It is especially noticeable at highway speeds when giving it more throttle. The engine is shaking but goes away when I let off the gas. So Far:
-All plugs were changed with motorcrafts about 30,000 miles ago along with boots and springs.
-Coils were replaced a few years ago (~20,000 miles ago) with cheap amazon coils. I had a misfire and replaced with these and it went away.
-I just replaced both VCT solenoids trying to fix this issue. No difference.
-I just cleaned throttle body with TB cleaner, cleaned MAF with MAF cleaner, air filter. No difference.
I am not getting any codes even after checking. My fuel pressure is right were it should be ~39-40 PSI. This honestly feels like ignition misfire because what else could it be? But shouldn't there be a definite code if it were a misfire? Can the coils develop issues without giving a code?
To start, my truck 2004 5.4, over the past few months has begun to stutter under loads. It is especially noticeable at highway speeds when giving it more throttle. The engine is shaking but goes away when I let off the gas. So Far:
-All plugs were changed with motorcrafts about 30,000 miles ago along with boots and springs.
-Coils were replaced a few years ago (~20,000 miles ago) with cheap amazon coils. I had a misfire and replaced with these and it went away.
-I just replaced both VCT solenoids trying to fix this issue. No difference.
-I just cleaned throttle body with TB cleaner, cleaned MAF with MAF cleaner, air filter. No difference.
I am not getting any codes even after checking. My fuel pressure is right were it should be ~39-40 PSI. This honestly feels like ignition misfire because what else could it be? But shouldn't there be a definite code if it were a misfire? Can the coils develop issues without giving a code?
I had the knock sensors replaced. Same sluggishness under load. No codes thrown. One of the knock sensors had a wire cut.
2006 5.4 XLT