I have 2006 gmc 5.3 multiple miss fires on left bank. Code p300
Changed everything I can think of wires, plugs, manifold gaskets, injectors, Corel, lean
gas tank, check for water in fuel. Sound like a valve in a old style motor. Check com
press on head check ok. Been to car dealer shop threes and not fixed yet. They say it
might this or that but it cost me every time I take it in.
After taking it to dealership one I took to twice couple thousand dollar later. I took the engine apart . I found 4 lifter that were shot and a cam shaft that look like it had been on grind. One bad value and a broke spring. Make you wonder who works at these dealship. Now what to fix it buy new engine. KEEP IN MIND I HAVE PUT OVER A COUPLE THOUSAND . NEW ENGINE 3500 to 4500. I read this engine are bad for bad cam breaking and thing like this. Sometime it better to go with your gut feeling. To save some money.
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