Hello,
I purchased a 2007 Trailblazer LS with the 4.2L I-6 with 124,000 miles that was being sold due to a engine noise (sounds like rattling then it makes a clang).
I removed the serpentine belt and started the vehicle and the noise did not change.
I replaced the Camshaft Position Actuator Solenoid (CPAS) with a Dorman part and this did not change the noise.
I removed the starter and the bolts in the flexplate to the torque converter are all tight. I can not see enough of the flexplate to verify that it is not cracked (so, I suppose if the flexplate is cracked it could cause this noise?).
I removed the valve cover and noticed a light wear mark (that pretty much just removed the yellow film) on the inside top of the valve cover (directly over the timing chain). The 2007 I4.2 does not have a top timing chain guide! I went to the dealer and verified this!
Do you think this (timing chain hitting the vale cover) is causing the noise the engine is making?
Due to the wear mark on the inside top of the valve cover, I believe I will have to install a new chain and possibly a phazor!
If you have any recommendations, please let me know what they are?
Thanks,
Paul
I purchased a 2007 Trailblazer LS with the 4.2L I-6 with 124,000 miles that was being sold due to a engine noise (sounds like rattling then it makes a clang).
I removed the serpentine belt and started the vehicle and the noise did not change.
I replaced the Camshaft Position Actuator Solenoid (CPAS) with a Dorman part and this did not change the noise.
I removed the starter and the bolts in the flexplate to the torque converter are all tight. I can not see enough of the flexplate to verify that it is not cracked (so, I suppose if the flexplate is cracked it could cause this noise?).
I removed the valve cover and noticed a light wear mark (that pretty much just removed the yellow film) on the inside top of the valve cover (directly over the timing chain). The 2007 I4.2 does not have a top timing chain guide! I went to the dealer and verified this!
Do you think this (timing chain hitting the vale cover) is causing the noise the engine is making?
Due to the wear mark on the inside top of the valve cover, I believe I will have to install a new chain and possibly a phazor!
If you have any recommendations, please let me know what they are?
Thanks,
Paul