Same Envoy with a dying (but not dead) oil pump and major oil leak.
Drove it all over Colorado last weekend. Monday morning Mrs Cad calls me and the truck engine is making popping sounds, smoke and a burning oil smell. That night I check it and the smoke is coming down from near the bottom of the timing cover. Oil pump dead? Nope have pressure. Is the belt moving? Yes so that not it. Water pump issue? Nope. Eventually the smoke stops and the truck is working fine. So what was it?
Found out last night that the truck AC is no longer working. All of the sudden it makes sense. Somehow (blown seal? hose leak?) all the refrigerant and maybe AC oil (or the smell was motor oil from the leak) got all over the timing cover and Monday morning was it burning off.
- Does this sound plausible?
- So what failed?
- To answer number 2, what should I look for?
- In terms of repair costs as a whole I was thinking there may be a possibility of letting the pump fail and replacing the block when it does considering the cost of fixing the pump and leaks is effectively the same price as a new block. But considering the 200,000 miles on all of the other pieces (tranny, shocks, differential, etc.) that are currently fine, am I better off just not getting the AC repaired and when it dies, sell the truck for parts/scrap.
AC compressor seized and burned up? AC belt (if it has a separate belt) kept trying to turn against resistance, overheated and stunk?
My guess as well. The Envoy may have a separate AC belt depending on the engine. I think the 5.3 has a separate belt and the 4.2 doesn’t.
I will check that but if that’s the case why did it stop? I will look for a broken belt.
My 5.3 Suburban has a separate belt for the AC, so if the Envoy has a similar engine it might, too. One day my AC belt broke soon after I started the engine, with a muffled bang and thump. Then the AC didn’t work. It took me a while to figure it out, because the belt landed inside some body work, so I didn’t find it until crawling underneath with a flashlight. Fortunately for me, the AC compressor spun freely, and the belt had just broken due to age. It only lasted 20 years and 195,000 miles.
On the 5.3l engine, if I remember correctly, the AC compressor is low on the passenger side. It’s a relatively large cylindrical thing, with a wheel on the front, and (probably) metal pipes running in and out of it.
If the compressor seized up, then the belt probably would have smoked before finally breaking. Unfortunately that means a new compressor, and likely other new parts, as a busted compressor could very well have sent pieces throughout the rest of the AC system.
It does have a separate belt. I changed it when I replaced the water pump last year.
Checked this morning. Yep, belt is gone. I’ll assume a seized compressor.