Why would my 99 blazer run fine for a couple minutes and then spit and sputter out and backfire through the throttle body. I had water in the tank. I then dropped the tank and emptied out all the gas and I have changed the throttle position sensor, spider injection, fuel filter, distributor, roter and cap. Any ideas? Someone help me.

 

I recently bought a 2000 blazer 4x4 for $150. I was told it was working then the next day it would not.
I preformed a series of checks on the fire delivery. And found the distributor needed to be replaced because the rotor had been unscrewed and caused damage to the mounting surface of the rotor as well as the damage to the distributor cap.

I also found an accessory hot wire that had been cut. After replacing the distributor and replacing the accessory hot wire. It cranked up. But it wasn't running right.

I preformed a tune up on it, plugs, plug wires, EGR.
And it still ran like it was missing on cylinders.

Then I preformed a compression test and found #6 cylinder with no compression. And #5 cylinder with almost no compression.

So I bought another blazer that was a 1997 for $300. I pulled the heads off and put them on the 2000 model blazer with new head gaskets and intake gaskets ". Finding out that your not supposed to adjust value lash on the rocker arms. They have been engineered to be torqued to 20 ft lb"

Once I got everything back together. The 2000 model is running great.

A multiple misfire is one of these bad head gaskets
Stuck valves
Bad distributor
Bad plugs
Bad plugs wires
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