direct cause of my low compression?

2004 CHEVROLET IMPALA
190,000 MILES • 3.8L • V6 • 2WD • AUTOMATIC
Avatar
RYDER1477
After replacing everything easily accessible that could have been related or direct cause of my low compression, loud operating, horrible fuel mileage issues, it has been confirmed the rear exhaust manifold gasket needs to be replaced. So, i was curious if there was an easier way to do it besides taking everything i just put on or replaced just to get to it.
Jul 3, 2025 at 9:12 AM
Advertisement
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,502 POSTS
  • ASE Certified Mechanic
Low compression cannot be caused by the exhaust manifold, FYI. Can you upload a video of the engine so I can hear it? To me it sounds like you have a timing chain issue. This will cause the noises and other problems you have described. Please go over this guide as well:

https://www.2carpros.com/articles/the-reasons-for-low-compression

Please go over this guide and get back to us.



Jul 4, 2025 at 5:08 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.