Knocking sound (video) and question about COP setup,
#1
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Year: 1989
Model: Cherokee
Engine: 4.0 L
Knocking sound (video) and question about COP setup,
So, my 4.0 started making this knocking/rattling a few weeks ago. I can't tell what it is, it is everywhere when I try to listen. Can a water pump make that sound? Or is it more likely valvetrain related. There is an exhaust leak at the manifold, and I get an occasional misfire, but other than that there has been nothing wrong with this engine.
Second, how difficult would it be for me to convert my '89 to a COP (coil on plug) type setup? I like the simplicity of it. Much less to go wrong than in a cap and rotor setup. Some people have a very negative opinion on the COP setup, but the way I see it, newer is better. Less maintenance is required with coil on plug systems.
Second, how difficult would it be for me to convert my '89 to a COP (coil on plug) type setup? I like the simplicity of it. Much less to go wrong than in a cap and rotor setup. Some people have a very negative opinion on the COP setup, but the way I see it, newer is better. Less maintenance is required with coil on plug systems.
#2
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Year: 1989
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Forgot to mention!
5 speed, so it isn't the flex plate bolts. 227,500 miles on it. No oil leaks, oil level good, no noticeable changes in performance since the rattle began.
5 speed, so it isn't the flex plate bolts. 227,500 miles on it. No oil leaks, oil level good, no noticeable changes in performance since the rattle began.
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I'd remove the serpentine belt and start it and see if the noise is still there. Also a good time to check the water pump for looseness in the shaft and the bearings in the idler pulley and alternator.
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And if it is still making the noise, look very carefully at the balancer pulley.
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