Weird engine noise 89 Ignition? Lifters?
Thread Starter
Cruising
Joined: Jun 2012
Posts: 14
Likes: 0
Weird engine noise 89 Ignition? Lifters?
Hey guys!
My brothers 1989 Coupe developed a weird engine noise and we don't know where it comes from. We made a video of the engine running:
He recently had his brake master cylinder, serpentine belt (with tensioner), knock sensor, power steering hoses, radiator hoses, thermostat and ATF changed. We replaced the battery couple of weeks ago. His cooling system looses coolant. We pressure tested it but it holds pressure fine. Also the heater is not producing heat.
He drove about 60 miles after all that. When he wanted to go for a drive the next day the engine started to sound like in the video. He did not drive the car because of the sound. When we wanted to try it again the next day the new battery was completely empty. Jump started the car and it still makes that noise.
I suspected too much ignition timing. We tested the base ignition timing and it was right at 6 degrees btdc where it should be.
Does it sound like it's running on all cylinders? Or is that a hydraulic lifter tapping?
Any help would be appreciated! Thanks!
Florian
My brothers 1989 Coupe developed a weird engine noise and we don't know where it comes from. We made a video of the engine running:
He recently had his brake master cylinder, serpentine belt (with tensioner), knock sensor, power steering hoses, radiator hoses, thermostat and ATF changed. We replaced the battery couple of weeks ago. His cooling system looses coolant. We pressure tested it but it holds pressure fine. Also the heater is not producing heat.
He drove about 60 miles after all that. When he wanted to go for a drive the next day the engine started to sound like in the video. He did not drive the car because of the sound. When we wanted to try it again the next day the new battery was completely empty. Jump started the car and it still makes that noise.
I suspected too much ignition timing. We tested the base ignition timing and it was right at 6 degrees btdc where it should be.
Does it sound like it's running on all cylinders? Or is that a hydraulic lifter tapping?
Any help would be appreciated! Thanks!
Florian
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 113
From: Michigan
Sounds like an exhaust leak to me kinda, but video isn't always as good as standing next to it.
I'd remove the valve cover, if nothing obvious pull the coil wire and turn then engine over and make sure all the rockers are going up and down. All that noise it'd have too be a broken valve and be a lot of damage at this point.
I'd remove the valve cover, if nothing obvious pull the coil wire and turn then engine over and make sure all the rockers are going up and down. All that noise it'd have too be a broken valve and be a lot of damage at this point.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
I would check for exhaust leaks first. Get s small diameter hose about 3 feet long and use it as a stethoscope with one end in your ear. Use the other end to go around and under the exhaust manifold at each cylinder. If it is an exhaust leak, you should hear it.
Then check the valve train if you don't find an exhaust leak. Use the same hose and pull out the PVC valve from the driver's valve cover and place the hose in there...is the sound louder? Then try the passenger's side by removing the fill cap and listen on that side. If you can identify the side, then remove the valve cover and check out all the rocker arms.
Look for exceptionally loose arms, or with the engine running (expect oil to get onto the exhaust and smoke) use the hose again and move from arm to arm.
Then check the valve train if you don't find an exhaust leak. Use the same hose and pull out the PVC valve from the driver's valve cover and place the hose in there...is the sound louder? Then try the passenger's side by removing the fill cap and listen on that side. If you can identify the side, then remove the valve cover and check out all the rocker arms.
Look for exceptionally loose arms, or with the engine running (expect oil to get onto the exhaust and smoke) use the hose again and move from arm to arm.
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