Noises are impossible to correctly diagnoise unless heard. Take it to a garage.
bad axle joint or ball joints and turn stops can make popping
A plugged up fuel filter.
If it has a v-lsd it will.
i had the same proplem turn out to be the fuel pump
You might have a blown headgasket on top
for starters, your fuel filter may be fouled.
A front popping on the left of a 98 Blazer could be the brakes, steering, or wheel bearing. Check all three to find the cause.
Valves adjusted to tight. Firing order mixed up.
impala sluggish after second gear
check cat converter if it has 75000 miles or more
either your timing is off or your valves still need adjustment