2003 Chevy Trailblazer Accelerator vibration

Ok lets start with the simple and go from there ok. Are all the plug wires on good and tight? Are the plugs all in tight none are loose? Is the check engine light on? Have you check the spark plugs to see if any are bad? Are the O2 sensors all pluged in? Get back to me and we will go from there.

The check engine light is not on. I checked several plugs and they appear good. The O2 sensor was just replaced about 6 months ago and the wires appear intact. I have noticed one additional thing. The vibration in the accelerator pedal is only when it is below 2000 rpm. At any point the rpm's are above 2000 and I press on the pedal the vibration is gone. Is there anything that could have been moved or affected when they put in the new front differential?

From what I can find no reason why the work done on the front diff should have caused any problems. Did you check to make sure no wires got pinched anywhere. If all looks good there maybe we can test the TPS if you have a digital multi meter. Let me know what you would like to do.

My vibration started after I had a new radio and remote starter installed. Could something have happened during that installation to cause the vibration? I have a 2008 TB LT

kibader, there is a chance that the installers knocked wires loose from a sensor. Does the rpm sound or feel like it's varying? If so, check for vacuum leaks, check and clean the EGR and IAC valves.

You can try and clean the throttle body out it could have some carbon build up causing a idle issues. Just use a rag and some throttle body cleaner and see if it gets better. And your cars doesn't have plus wires on it. It's s coil over plug system