My Suburban died last night!

[spinning wheels]

If its not firing on all cylinders, check for a broken distributor cap. Sometimes the HEI caps get a hairline fracture and thats all it takes to make them run like chit. Also, start it up at night, sometimes you can see if you have bad plug wires that may be arching on something like exhaust manifolds. My truck started running like chit, turned out to be a plug wire got burned on the exhaust manifold. Replaced it, and she was back in business.