Engine oil leak after the truck sits parked for four or more hours?

2003 GMC SONOMA

199,000 MILES • 4.3L • 6 CYL • 2WD • AUTOMATIC

DOOB

MEMBER
72 POSTS

It leaks oil mostly after it sits with engine off for appx 4+ hours. i know it has a front intake leak, but it seems to be coolant. And oil pressure appears to be low it starts out at 40 PSI then drops to about 20 PSI don't know if it's the sender or really low pressure. Thinking about replacing intake gasket but if can't stop oil leak what's the point i read can't pull oil pan on these trucks without pulling the engine... don't know if I'm up for that. guess I'll clean the bottom of motor then trace out the leak hope it's not main seal or the pan you guys know what else to look for that may be leaking on these 2003 4.3s thanks again

Apr 7, 2024 at 2:10 AM

STRAILER

✓Experienced Mechanic
55,540 POSTS

If the intake manifold is leaking that is where I would start. Also, check the oil filter and oil pan drain plug. I have also seen the oil pressure sender leak as well. The oil pressure is okay so I would not worry about that. This guide can help:

https://www.2carpros.com/articles/engine-is-leaking-oil

Please upload pictures or videos in your response to the problem so we can see what's going on. Here are the instructions on how to replace the intake manifold gaskets. Check out the images (below).

Images (Click to enlarge)