Slowfinger
Active Member
*Update* Hi, just got back from work, and every time I hit the gas, it would start knocking around 2000 - 3000 rpm. Got home and tried it in neutral, same, but not as bad. Will post video soon!
(Quick stats: 2002 Accord Coupe, F23A1 w/ 5spd, only 120,000Kms!)
Problem: Noticed very faint knocking sound about 8 months ago, it would come and go. The sound can be best described as a helicopter/knocking type sound. It is not sharp, or heavy.
I took my mechanic buddy for a spin about a month ago, but couldn't reproduce the sound.
About two weeks ago I noticed the sound linger a bit longer than normal, even when I drove the car for an extended period of time or when I revved it around the 2000 rpm range (±300) when in neutral, the knocking was still there.
My Diagnosis attempts:
1) Tried to isolate the noise by using a mechanic's stethoscope and placed it all over the engine, but from the top I could not hear the sound as definitive as I wanted it to be.
2) I did pull the plugs one at a time while it was revving at the rpm range. The sound was still there, I wonder if this rules out Rod Knock?
3) I mean the car has big-time pep, idles awesome, doesn't use up oil. Which brings me to last weekend, I ended up draining the oil (even though there was about 3000kms left before the next change), there was nothing noticeable when I strained it, the magnetic plug showed nothing, I even gently stuck a wire in the oil pan hoping to pull something out, but nothing except clear oil!
4) I've tested that it may be the transmission, but it still does it when you depress the clutch. The oil light has never been on. I don't drive my car too far, as my commute is only about 10 min driving tops!
Dealer Test: Senior mechanic's diagnosis, the sound was located from the bottom end (you could hear it big time compared to when listening from the top). The sound was located behind the shallow part of the oil pan, on the side where the transmission is attached. *We had to drive around for a bit to get the car warmed up good, before it started.
Dealer Diagnosis: The mechanic said it was most likely the thrust bearing for the crankshaft, as the car is a 5spd. >> But wouldn't the knocking be deeper & more pronounced. He said this is somewhat common and not to worry.
Final Thoughts:
1) I still think I may end up removing the oil pan just to be sure that it may not be something loose like the windage tray or some bracket of some sort.
2) I wonder if maybe the opposite end (not the timing belt side) of the balance shafts can be doing this.
3) This morning it wasn't that loud, and even on my way back home, nothing really noticeable. Sometimes it seems like the hotter the engine the noisier.
4) This is why I figure I'd change the oil prematurely, in case there was something going on with the previous oil. I had synthetic in before, and now put some 50/50 just to see if there was any difference. I know it can't be the type of oil as long as you use an API rated oil that is SJ or newer.
Video:
http://www.youtube.com/watch?v=DwzIRKkgRvg&feature=youtu.be
Would rather fix the problem, then have to re & re a new engine!
Any suggestions/comments/ideas would be greatly appreciated!
Thanks for your time!
(Quick stats: 2002 Accord Coupe, F23A1 w/ 5spd, only 120,000Kms!)
Problem: Noticed very faint knocking sound about 8 months ago, it would come and go. The sound can be best described as a helicopter/knocking type sound. It is not sharp, or heavy.
I took my mechanic buddy for a spin about a month ago, but couldn't reproduce the sound.
About two weeks ago I noticed the sound linger a bit longer than normal, even when I drove the car for an extended period of time or when I revved it around the 2000 rpm range (±300) when in neutral, the knocking was still there.
My Diagnosis attempts:
1) Tried to isolate the noise by using a mechanic's stethoscope and placed it all over the engine, but from the top I could not hear the sound as definitive as I wanted it to be.
2) I did pull the plugs one at a time while it was revving at the rpm range. The sound was still there, I wonder if this rules out Rod Knock?
3) I mean the car has big-time pep, idles awesome, doesn't use up oil. Which brings me to last weekend, I ended up draining the oil (even though there was about 3000kms left before the next change), there was nothing noticeable when I strained it, the magnetic plug showed nothing, I even gently stuck a wire in the oil pan hoping to pull something out, but nothing except clear oil!
4) I've tested that it may be the transmission, but it still does it when you depress the clutch. The oil light has never been on. I don't drive my car too far, as my commute is only about 10 min driving tops!
Dealer Test: Senior mechanic's diagnosis, the sound was located from the bottom end (you could hear it big time compared to when listening from the top). The sound was located behind the shallow part of the oil pan, on the side where the transmission is attached. *We had to drive around for a bit to get the car warmed up good, before it started.
Dealer Diagnosis: The mechanic said it was most likely the thrust bearing for the crankshaft, as the car is a 5spd. >> But wouldn't the knocking be deeper & more pronounced. He said this is somewhat common and not to worry.
Final Thoughts:
1) I still think I may end up removing the oil pan just to be sure that it may not be something loose like the windage tray or some bracket of some sort.
2) I wonder if maybe the opposite end (not the timing belt side) of the balance shafts can be doing this.
3) This morning it wasn't that loud, and even on my way back home, nothing really noticeable. Sometimes it seems like the hotter the engine the noisier.
4) This is why I figure I'd change the oil prematurely, in case there was something going on with the previous oil. I had synthetic in before, and now put some 50/50 just to see if there was any difference. I know it can't be the type of oil as long as you use an API rated oil that is SJ or newer.
Video:
http://www.youtube.com/watch?v=DwzIRKkgRvg&feature=youtu.be
Would rather fix the problem, then have to re & re a new engine!
Any suggestions/comments/ideas would be greatly appreciated!
Thanks for your time!
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