2003 Chevrolet Trailblazer running rough

2003 CHEVROLET TRAILBLAZER
128,000 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC
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JIBJABME
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The truck started running rough and then the check engine light came on. I put it on a computer and the only code was a ph300 i think. So i put a new coil on number one along with all new spark plugs. It ran like a new motor. later on that same day it started running rough again, and a new code said it was the cam sensor and map sensor. I put the cam sensor but it still ran rough. I hooked the computer back on and the code said i needed a cam sensor again the only code this time. I also cleared the computer six or more time by unhooking the positive battery cable. In short,the truck will run great for awhile and then it starts running rough with the RPM running up and down. I put it in neutral to keep it running. Last night I was on the freeway for half hour,it ran great until i pulled in the driveway and it started running rough but no light came on. This morning went to work it started up and ran great........What do you think it might be?
Dec 28, 2014 at 2:31 PM
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JOHNNYT73
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What exactly is the code number it is giving you? Are you sure it is not calling for the variable valve timing solenoid?
Dec 28, 2014 at 3:07 PM
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JIBJABME
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I don't remember the code but it was the camshaft sensor, the man at the parts store showed me the the computer. its been doing this for about four days now. But today the light hasnt come on yet ,so their is nothing to check. If the light comes on again I will drive it back to the parts store and put it on the computer.
Dec 28, 2014 at 3:49 PM
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JOHNNYT73
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Please be weary of Parts store employees lol. Unless they have an actual background in being a technician.
Dec 28, 2014 at 3:58 PM
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JIBJABME
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no. they were on the level. They cant figure it out either. What do you think it might be?
Dec 28, 2014 at 4:10 PM
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JOHNNYT73
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It could be the variable valve timing solenoid. You could also trying removing the throttle body (very simple on these trucks) and cleaning both sides of it to see how it does. Does it seem to run better after an oil change?
Dec 28, 2014 at 4:23 PM
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JOHNNYT73
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If you can get the code again, that would be helpful and just let me know.
Dec 28, 2014 at 4:28 PM
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JIBJABME
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okay I will give it a try and clean throttle body. I will get back with you tomorrow.Thanks
Dec 28, 2014 at 4:37 PM
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JOHNNYT73
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Were you able to get the issue resolved?
Jan 24, 2015 at 4:16 PM