Rattle in motor
Asked by Jboggess34 Oct 11, 2019 at 07:38 AM about the 2006 Chevrolet Trailblazer LS RWD
Question type: Maintenance & Repair
My car is making a rattle noise from some
where inside the engine. It sounds something
like a rattling catalytic converter. It started
very light and is now getting louder. More
loud when then engine is shifting gears or at
a higher rpm. Engine has same power and
performance. I was thinking it was possibly a
bearing from somewhere on the serpentine
belt.
8 Answers
Jboggess34 answered 5 years ago
I guess I will try running a diagnostic test to see if I can get some information there.
Jboggess34 answered 5 years ago
Also, this problem started after I put full synthetic oil in it for the first time. I’m sure that don’t make a difference but it wasn’t making that noise before.
Jboggess34 answered 5 years ago
Ed so if this was a problem due to the synthetic oil and I have a oil flow issue. How can this be fixed? And I am not messing around at all. That’s why I am trying to find the problem so I can fix it. I can fix most things myself. However an oil flow problem sounds difficult. Would this be something super lube could flush out? Thanks for all the help by the way.
Wow, the nerve of some people. Since you said rattle like a cat, it's not the engine itself but rather an accessory in my opinion. Like a pulley, like a heatshield, like a fan clutch, fan shroud. Our platform has it's quirks, but a spun bearing or internal engine failure on the 4.2 sounds nothing like a rattling cat. Perhaps get an automotive stethescope, which are dirt cheap, listen around the serpentine belt. We have weird noises that will come from the idler pulley, tensioner, fan clutch/waterpump area. Also, the heat shield on the exhaust manifold can rattle.
If the noise is coming from inside the engine and it sounds like its at the serpentine belt, it might be in the timing belt or chain. If this breaks, it can ruin the engine. Ed, great that you so caring to look out for this person in spite of what that idiot FJ4072 is saying - I agree, learn to read before mouthing off. Nerve?
Jboggess34 answered 5 years ago
Well, I finally figured out what the problem was. I took the serpentine belt off, crunk it up and the noise was gone. Turn all my pulleys and found the water pump was making the noise. I purchased the water pump and a new serpentine belt for $60 and some change and I changed it out. It took me about an hour to do since I have done it before about 80,000 miles ago. Needless to say at 231k miles she is purring like a kitten! Thanks for all the help guys!
