I bought a 94 4runner, the vehicle has 128,000 miles. The engine seems good when I bought it, no knock and all the belts including the timing were changed at least 42k ago. However, I noticed a slight knock coming from the plenum area or the top block.It's noticeable around 1,500-2,000 and above that seems to go away and disappear.
I ended up taking the 4runner to the Toyota dealership, the mechanic stated that he heard a ' knocking type of noise from the rear, sounds like a piston' The dealer quoted me at 4k to just tear down and inspect.( He heard it by ear)
The vehicle I bought has a warranty a from the used car dealership(not Toyota), and the work must be performed at their mechanics per contract. Well, their mechanics claimed it was " Valve shims being at maximum spec and a collapsed valve lifter" So they went ahead and adjusted the valves and the lash adjuster etc. After I went to pick it up I noticed on the invoice they switched to 20W50 weight oil. I asked them why did that opposed to the regular 10W40? the shop managers response was " A Toyota tech recommended this weight"
So for the most part the sound went away for the next couple of days I've had it back. But When I made a long trip on the interstate, I noticed it came back when I pulled off at slow speeds. Around 1,000-1500 it's a dull type of knocking sound, or somebody hitting their fingers against a fan blade.
This is how it sounded before it was fixed. It's making that same sound just not as loud. Wrist pin knock? I think if it was a rod, wouldn't that have gone out along time ago?
Someone also made the comment that a faulty EGR valve could be making sound inside the plenum. Any thoughts or opinions are welcomed.
heres some videos I took
http://youtu.be/LdmhoDKFzi8
http://youtu.be/DfSYPkCnMic
I ended up taking the 4runner to the Toyota dealership, the mechanic stated that he heard a ' knocking type of noise from the rear, sounds like a piston' The dealer quoted me at 4k to just tear down and inspect.( He heard it by ear)
The vehicle I bought has a warranty a from the used car dealership(not Toyota), and the work must be performed at their mechanics per contract. Well, their mechanics claimed it was " Valve shims being at maximum spec and a collapsed valve lifter" So they went ahead and adjusted the valves and the lash adjuster etc. After I went to pick it up I noticed on the invoice they switched to 20W50 weight oil. I asked them why did that opposed to the regular 10W40? the shop managers response was " A Toyota tech recommended this weight"
So for the most part the sound went away for the next couple of days I've had it back. But When I made a long trip on the interstate, I noticed it came back when I pulled off at slow speeds. Around 1,000-1500 it's a dull type of knocking sound, or somebody hitting their fingers against a fan blade.
This is how it sounded before it was fixed. It's making that same sound just not as loud. Wrist pin knock? I think if it was a rod, wouldn't that have gone out along time ago?
Someone also made the comment that a faulty EGR valve could be making sound inside the plenum. Any thoughts or opinions are welcomed.
heres some videos I took
http://youtu.be/LdmhoDKFzi8
http://youtu.be/DfSYPkCnMic
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