How to Fix low compression?
Asked by LogansWar Mar 24, 2023 at 02:19 PM about the 2005 Saturn VUE Base
Question type: Maintenance & Repair
For a couple months, had trouble starting.
Also RPMs would drop and/or run low while
idling or when letting off gas. Then, a couple
hours after driving it, it wouldn't start at all.
Mechanic checked engine, discovered all four
cylinders had low compression!
What should I check or do to fix?
3 Answers
First, have another mechanic check out the problem. This could be caused by several things, like a vacuum leak. Maybe the mechanic just doesn't want to work on your old POS unless he can make real money off you. compression problems depending on what's causing them, can be corrected in different ways. It depends on what's actually wrong. The engine might be worn out, or you have loose, carboned valves, or a head gasket problem.
18 year old Saturn, chances are very high that the engine is just worn out, they were not the best even when they were in production. You can do a dry then wet compression test if your wondering if it rings or valves. But it sounds like it ready for the scrap heap.
This is a classic symptom of a jumped timing chain or belt. If you have a timing belt it's probably broken. Either way before you put any money into it see if you have an interference engine. If you do, the pistons have surely slammed into the valves when the timing chain jumped or the timing belt broke and the engine is done. Hope that helps! Jim