Been driving on it for over a year with no perceivable issues other than the sound itself. Sound goes away when it rains which is really weird. I’ll take off the heat shield and take a look at the exhaust manifold.oh man....that sounds bad....
Im leaning towards possible rod knock. it sounds a bit lower pitched to me,...valve would usually be higher pitched....
the mechanic couldnt diagnose it?
Make sure exhaust is all tight / plugs are not loose... had a loose plug that made a compression leak that sounded just like rod knock.
Since your compression #'s are all consistent and do not change dry vs. wet - I would verify mechanical timing marks (crank, cam, pull #1 spark plug and insert dowel or thin-blade screwdriver to watch rise/fall to confirm mechanical #1 TDC ... before condemning the motor.160 PSI on all cylinders hot and cold. 110k on the odometer.
There is an exhaust donut between the exhaust manifold / primary cat converter <-> and the front pipe: to access the donut, you will need to drop the front pipe off the exhaust manifold from underneath. re: sound goes away during rain: that may indicate a failing flex pipe, which is part of the front pipe assembly, visible from underneath.Been driving on it for over a year with no perceivable issues other than the sound itself. Sound goes away when it rains which is really weird. I’ll take off the heat shield and take a look at the exhaust manifold.
My bad. Meant to link the video. Here is the sound.
link
Not the Flex pipe. There was an exhaust leak at the flex pipe last year and I put in a new flex pipe. Ticking noise hasn’t changed during any of it. I’ll check the donut and the manifold.There is an exhaust donut between the exhaust manifold / primary cat converter <-> and the front pipe: to access the donut, you will need to drop the front pipe off the exhaust manifold from underneath. re: sound goes away during rain: that may indicate a failing flex pipe, which is part of the front pipe assembly, visible from underneath.
Agree w/ 1990toyota, the noise sounds like it could be exhaust: if no driveability or other issues, I'd check the exhaust manifold, exhaust donut, and front pipe first, if it was here.
Took it to a mechanic a year ago and he said he “didn’t notice the sound while taking it for a test drive” and “the valves look fine”. Retorqued the plugs before the video was takenoh man....that sounds bad....
Im leaning towards possible rod knock. it sounds a bit lower pitched to me,...valve would usually be higher pitched....
the mechanic couldnt diagnose it?
Make sure exhaust is all tight / plugs are not loose... had a loose plug that made a compression leak that sounded just like rod knock.
If it was a spun bearing, would there be other symptoms? I’ve been driving on it for over a year and it hasn’t got noticeably worse.I would get a mechanics stethoscope and listen at the valve cover, the head, the block, and the oil pan. I agree that to me, it sounds like a piston rod journal bearing was spun so there is a pounding on the crankshaft journal every time the piston changes direction. But a way to verify is with such a mechanics stethoscope.
Spun bearing would sound worst at the head? Or at the oil pan?I would get a mechanics stethoscope and listen at the valve cover, the head, the block, and the oil pan. I agree that to me, it sounds like a piston rod journal bearing was spun so there is a pounding on the crankshaft journal every time the piston changes direction. But a way to verify is with such a mechanics stethoscope.
Yes, this symptom would seem to point first towards valve stem seals leaking. Wouldn't have anything to do with the ticking noise you are hearing.Another bit of info that might be unrelated: car sat for a few days, cranked but didn’t start on the first try. Started on second key turn with trouble and send some burnt oil out of the exhaust pipe for a few seconds. To me with my basic knowledge, that screams valve stem seal problems. Any thoughts?
A spun rod bearing would sound loudest at the block, and to a lesser extend, the oil pan. It would not sound as loud at the head, where you would pick up more of the valve noise typical on that engine. I'm talking about the sound you would hear using a mechanic's stethoscope.Spun bearing would sound worst at the head? Or at the oil pan?
Timing belt has not been changed to my knowledge. Inherited the car 8 or 9 years ago. 106k on the odometer.Since your compression #'s are all consistent and do not change dry vs. wet - I would verify mechanical timing marks (crank, cam, pull #1 spark plug and insert dowel or thin-blade screwdriver to watch rise/fall to confirm mechanical #1 TDC ... before condemning the motor.
How many years / miles on the timing belt?
