Recently, my mom had some complaints about how our Tahoe was running. Somewhat sluggish and a rough idle. that went on for awhile because I assumed it was a vacuum leak that I really didn’t have time to fix at the moment. Time went on and then I get a call from my mom and she says that its overheating badly and she’s on the side of the road letting it cool down. I figured the thermostat went out again or was stuck open. She comes back home and says its smoking really bad, I went outside to look into it and sure enough. The Tahoe would hardly start at all and when I did get it to run and stay running for a minute, it was smoking from the back of the engine and from the exhaust. It smelled like burnt coolant and when examining the exhaust manifold on the passenger side, I could see water dripping onto the area where the manifold meets the exhaust. That’s how it was shooting water and coolant out of the exhaust. So, at this point, I’m thinking blown head gasket and praying its not cracked heads. A friend of mine let me borrow his trailer and he took it to school for me. I started by removing the intake and all, obviously, and when I removed the thermostat, it smelled like barbeque. Straight up, bottom of the grill type aroma. Which is a huge indicator of a blown head gasket, the smell is actually the product of built up combustion gases. Then I removed both heads, thinking id probably have it all back together the following day, I was excited to clean them and get started putting everything back together.. but no.. both heads turned out to be cracked. from the exhaust valve to the water port. So, now, I’m hunting for some 305 heads for my 350. Lesson: Always take a closer look!
