Knocking = Potential Engine Problem?
09-17-2003 | 06:31 PM
#11
Thread Starter
Junior Member
Joined: Sep 2003
Posts: 13
Likes: 0
Originally posted by AccordManiac
I would say.. time for valve adjustment..
I would say.. time for valve adjustment..
But, if I'm not mistaken, it is important for the valves to seat long enough to disipate their heat. So keeping them adjusted is probably important.
09-17-2003 | 07:40 PM
#12
Mr Clutch
Joined: Apr 2003
Posts: 786
Likes: 0
From: In your girls....
Re: Knocking = Potential Engine Problem?
Originally posted by MrMJPEG
I'm hoping those of you who know something might be able to diagnose this for me.
When my '94 LX Wagon's engine is around 1200 RPM there's a knocking sound under the rocker panel. When I'm holding the throttle open I can feel the engine shake slightly, like it is missing a bit. It goes away as long as it isn't in a narrow band around 1200 to 1500 RPM.
Without knowing any better, it seems like the exaust vavle(s) on a cylinder are floating at this RPM and the knocking I'm hearing is exhaust. But if this is the case, why do HIGHER RPMs make the problem go away?
Valves were adjusted and timing belt replaced a year and a half ago at 80,000 miles by a Honda dealer ($$$). Gas mileage is fine and unchanged, car accelerates fine and has 120,000 miles. Exhaust is noisy under a load, but there seems to be no single source for the exaust sound other than the area around the exhaust manifold.
This might be pertinent: I have a pretty bad pinging problem that I'm going to attempt to tackle by getting a tuneup. When the engine is warm I sometimes get really bad pinging under a light load. Downshifting the automatic usually helps. I can't get the 3 distributor bolts loosened to try to retard the timing. I'd rather not have to resort to a higher octane fuel.
Thanks in advance!
I'm hoping those of you who know something might be able to diagnose this for me.
When my '94 LX Wagon's engine is around 1200 RPM there's a knocking sound under the rocker panel. When I'm holding the throttle open I can feel the engine shake slightly, like it is missing a bit. It goes away as long as it isn't in a narrow band around 1200 to 1500 RPM.
Without knowing any better, it seems like the exaust vavle(s) on a cylinder are floating at this RPM and the knocking I'm hearing is exhaust. But if this is the case, why do HIGHER RPMs make the problem go away?
Valves were adjusted and timing belt replaced a year and a half ago at 80,000 miles by a Honda dealer ($$$). Gas mileage is fine and unchanged, car accelerates fine and has 120,000 miles. Exhaust is noisy under a load, but there seems to be no single source for the exaust sound other than the area around the exhaust manifold.
This might be pertinent: I have a pretty bad pinging problem that I'm going to attempt to tackle by getting a tuneup. When the engine is warm I sometimes get really bad pinging under a light load. Downshifting the automatic usually helps. I can't get the 3 distributor bolts loosened to try to retard the timing. I'd rather not have to resort to a higher octane fuel.
Thanks in advance!
It's not your valves, they make a different noise than what you're hearing. Try not to worry too much, just change your oil regularly and try to do tune ups before thier time.
09-18-2003 | 08:25 AM
#14
Thread Starter
Junior Member
Joined: Sep 2003
Posts: 13
Likes: 0
Re: Re: Knocking = Potential Engine Problem?
Originally posted by Big Chaze
The sound you're hearing is coming from the main bearing. It almost sounds like your engine is snoring.
It's not your valves, they make a different noise than what you're hearing. Try not to worry too much, just change your oil regularly and try to do tune ups before thier time.
The sound you're hearing is coming from the main bearing. It almost sounds like your engine is snoring.
It's not your valves, they make a different noise than what you're hearing. Try not to worry too much, just change your oil regularly and try to do tune ups before thier time.
But I'll keep on the oil changes and make sure it is tuned up. Thanks!
09-18-2003 | 05:28 PM
#15
Senior Member
Joined: Jun 2003
Posts: 489
Likes: 0
From: Orlando, Florida
Now that I paid attention, I do hear my engine knocking between 1800-2,000 rpms while driving, and it does sound discomforting. I heard it while driving home from work, so I parked my car in the driveway, lifted the hood and reved the engine via throttle cable, sure enough, at 1800-2,000 rpms the knocking came in... it sounds like a grinding/knocking, and I can actually feel the engine vibrate a bit more when it comes in. From inside the car, holding the engine at a steady 2,000 rpms, it sounds like Im grinding coffee. If I rev higher, it tends to fade out. I dont know what I could have done to cause this sound to appear. The engine has close to 100,000 miles, mostly highway, and all run on Valvoline synthetic oil.
09-18-2003 | 06:44 PM
#16
Mr Clutch
Joined: Apr 2003
Posts: 786
Likes: 0
From: In your girls....
Originally posted by ItsaHonda
Now that I paid attention, I do hear my engine knocking between 1800-2,000 rpms while driving, and it does sound discomforting. I heard it while driving home from work, so I parked my car in the driveway, lifted the hood and reved the engine via throttle cable, sure enough, at 1800-2,000 rpms the knocking came in... it sounds like a grinding/knocking, and I can actually feel the engine vibrate a bit more when it comes in. From inside the car, holding the engine at a steady 2,000 rpms, it sounds like Im grinding coffee. If I rev higher, it tends to fade out. I dont know what I could have done to cause this sound to appear. The engine has close to 100,000 miles, mostly highway, and all run on Valvoline synthetic oil.
Now that I paid attention, I do hear my engine knocking between 1800-2,000 rpms while driving, and it does sound discomforting. I heard it while driving home from work, so I parked my car in the driveway, lifted the hood and reved the engine via throttle cable, sure enough, at 1800-2,000 rpms the knocking came in... it sounds like a grinding/knocking, and I can actually feel the engine vibrate a bit more when it comes in. From inside the car, holding the engine at a steady 2,000 rpms, it sounds like Im grinding coffee. If I rev higher, it tends to fade out. I dont know what I could have done to cause this sound to appear. The engine has close to 100,000 miles, mostly highway, and all run on Valvoline synthetic oil.
I dont think I heard it on the car when I first brought it. I hear it most right before 2nd gear kicks in.
My car has about 149 k on the odo. I put about 50k in 3 years, all highway.
09-19-2003 | 10:24 AM
#19
Mr Clutch
Joined: Apr 2003
Posts: 786
Likes: 0
From: In your girls....
Originally posted by lowelcam96
Have your EGR system checked.
passage could be clogged or partially clogged. A non-working EGR system does cause knocking sounds.
Have your EGR system checked.
passage could be clogged or partially clogged. A non-working EGR system does cause knocking sounds.