i have a 2001 blazer Lt with 133,000 miles and i have a gurgling sound coming from the exhaust when i first start it,it only happens when i start it after it sitting overnight,anyone have an idea of what it could be?

 

Possibly the heat shield or insides of your catalytic converter rattling.

 

I am having this same issue, did you find the results?
Thanks

 

Any check engine light? How does it run? Is the idle normal, or does it fluctuate? Is there any steam or water coming out the tailpipe?

 

No CEL, Run just fine/great, the idle is very steady. Water does come out of the tail pipe and muffler weepe hole during warm up only, after warm up no water.
I just checked the fuel pressure and is holds at 55psi for about 15-20 minutes and than very very very slowly drops down over about an hour or longer. I was thinking that the regulator was leaking fuel in the plenum and the excess fuel back firing in the exhaust, not sure.
Every thing else is great with this motor, LIM gaskets are fresh(about 1 year old) with the new aluminum ones. Great vacumm with the Transfer case vacuum switch relpaced and everything. I can say basically this is a great running engine with all the attention given to it as the typically need, all the work is done by me as I am **** with detail and quality.
Any suggestions would be greatly appreciated
Timing, octane, cloged cat/muffler.
I started a fresh thread before I searched and found this one.
Thanks

 

Problem solved, I just got done figuring it out. It was a warp/dimple/bow or what ever you call it in the outer shell(sheet metal) of the muffler. Kinda like a snapple lid or washing machine lid. It was basically vibration, once the muffler warms up the dimple goes away. When cold I was able to milipulate the dimple not be so concave in that spot. Kinda weird but that is what it was.
Thanks