bjslade0269

I believe I have a bad lifter on my 1999 4.6L. I used the stehescope and the noise is coming from the top end. When I get up to 5K range (very rare) I hear the valves making alot of noise. When I am driving normal I hear the suspected lifter noise during deceleration and sometimes lightly while accelerating.

Does ths sound like a lifter(lash adjuster) problem??

How hard are they to replace??

Would this affect my gas mileage??

guage

Sounds like worn valve guides (valves floating side to side due to worn guides). Lifters don't usually make noise in newer vehicles, besides you wouldn't want to replace them, not fun! You also could have a timing chain hydraulic adjuster that's weak that will cause a similar noise. Is your oil clean and topped up? Good luck!