97 blazer (260 thousand miles)hesitates after construction/traffic. When i try to get it go back to speed limit it hesitates will not go over 30/40 miles an hour. Have to pull it over turn it off and when I turn it back on starts right up and runs well. Took it to the garage after the first time it did it, mechanic said that he drove it cant get it to mess up.Has new spark plugs and coil wire. My 02 sensor my dad messed with so apparently that code will always show up as a problem. Sometimes i feel like i have to speed to keep it from feeling bogged down. HELP!

 

Funny you should mention this. After I lost the motor on my Bravada, I got involved with people who knew a thing or two about Blazers. Your scenario came up quite a bit in the discussions. According to what I've heard, it could be your 1-wire Knock Sensor either failing, or doing its job. on both counts.

 

Did you figured out the problem?

 

Needed some coolant but my dad told me it must be an electrical thing because it wouldnt have cooled down enough from just restarting the car. He said it would have taken atleast 20 minutes to cool down and run okay again. So better with more coolant but not 100% back to normal

 

You just don't need your coolant topped off for no reason. Find the source of leak ASAP! It could be your lower intake manifold gasket, head gasket, etc.

Take a look at my photo album if want to see what happens when you don't figure out a coolant leak promptly.

Wish you best of luck!