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-   -   What is this? Knocking Popping Tapping noise from the engine bay no codes (https://www.ft86club.com/forums/showthread.php?t=124401)

ermax 01-03-2018 12:20 PM

I also vote for valve train rather than bottom end. To rule out the pulley you are suspicious of, try running it without the belt for a few seconds.

humfrz 01-03-2018 12:54 PM

1 Attachment(s)
Quote:

Originally Posted by arren123 (Post 3023203)
Humfrz,

Give a listen to this one and let me know what you think. It's from a cold start the next day. It is pretty loud when I move to the passenger side.

https://youtu.be/6zrsWeDxsIE

Well, it still sounds like something in the valve train.

I'm guessing that one of these puppies has come unglued/weakened/broken.....:iono:


humfrz

Ultramaroon 01-03-2018 01:31 PM

Quote:

Originally Posted by arren123 (Post 3023203)
Humfrz,

Give a listen to this one and let me know what you think. It's from a cold start the next day. It is pretty loud when I move to the passenger side.

https://youtu.be/6zrsWeDxsIE

Augh, that shit is toast. I'm surprised it's still running on all 4.

That's a real bummer but it will get much worse if you keep running it. Valves are not meant to handle impact loads.

arren123 01-03-2018 02:15 PM

Quote:

Originally Posted by humfrz (Post 3023254)
Well, it still sounds like something in the valve train.

I'm guessing that one of these puppies has come unglued/weakened/broken.....:iono:


humfrz


Hopefully it is something in the valve train.. I'll take head work over bottom end work. That's assuming that the valve didn't mar up the top of the piston.

I'd expect a misfire code though and so far there are no codes.

humfrz 01-03-2018 02:27 PM

Quote:

Originally Posted by arren123 (Post 3023310)
Hopefully it is something in the valve train.. I'll take head work over bottom end work. That's assuming that the valve didn't mar up the top of the piston.

I'd expect a misfire code though and so far there are no codes.

I reckon that if a valve dropped far enough for the piston to hit it ........ the engine wouldn't still be running as well as it is ...... :iono:

Did you oil up or eliminate that idler pulley you first suspected ... ??

Have you taken it into the dealership as you mentioned you might do .. ??


humfrz

stevesnj 01-03-2018 03:17 PM

Doesn't the belt just run the alternator and AC? if so try removing the belt and start the car. No sound it's a pulley bearing or something stuck. It's very loud but check the exhaust gasket on that side if you can.Dunno how easy that is though. Weird thing is the engine isn't bucking or have a misfire sound like combustion or exhaust is affected.

Sportsguy83 01-03-2018 03:22 PM

Quote:

Originally Posted by stevesnj (Post 3023348)
Doesn't the belt just run the alternator and AC? if so try removing the belt and start the car. No sound it's a pulley bearing or something stuck. It's very loud but check the exhaust gasket on that side if you can.Dunno how easy that is though.

Alternator, AC and water pump. definitely a quick check is to run it without belt for a few seconds.

stevesnj 01-03-2018 03:26 PM

Quote:

Originally Posted by Sportsguy83 (Post 3023351)
Alternator, AC and water pump. definitely a quick check is to run it without belt for a few seconds.

Ah the water pump too.. Gotcha. Yeah a cold start would work

Ultramaroon 01-03-2018 04:35 PM

Quote:

Originally Posted by stevesnj (Post 3023352)
Ah the water pump too.. Gotcha. Yeah a cold start would work

No harm in running it without the belt for a minute, even at normal temp. Valid test.

arren123 01-03-2018 06:49 PM

OK. Here's what I found out so far.

I thought that a spark plug may have backed itself out so I checked #1 and #3 on the passenger side and they were tight. Then I pulled the plugs out. No clues from the plugs, they look normal. I didn't bother with #2 and #4 since those a difficult to remove with all the injector/supercharger hoses in the way.

I took off the belt and popped the charge pipe off the supercharger so the engine would get air. Started the car for a few seconds and still had the loud sounds. At least it eliminated quite a few things: pulleys, a/c, alternator, supercharger, etc...

Checked for anything loose and couldn't find any. Removed and broke off the main clip of the decorative Subaru intake cover (oops). Nothing loose under there.

No codes and engine seems to run smooth otherwise.

I have a diagnostic scheduled for Monday. Hoping they will have a loaner car for me as promised.

humfrz 01-03-2018 07:42 PM

Quote:

Originally Posted by arren123 (Post 3023454)
OK. Here's what I found out so far.

I thought that a spark plug may have backed itself out so I checked #1 and #3 on the passenger side and they were tight. Then I pulled the plugs out. No clues from the plugs, they look normal. I didn't bother with #2 and #4 since those a difficult to remove with all the injector/supercharger hoses in the way.

I took off the belt and popped the charge pipe off the supercharger so the engine would get air. Started the car for a few seconds and still had the loud sounds. At least it eliminated quite a few things: pulleys, a/c, alternator, supercharger, etc...

Checked for anything loose and couldn't find any. Removed and broke off the main clip of the decorative Subaru intake cover (oops). Nothing loose under there.

No codes and engine seems to run smooth otherwise.

I have a diagnostic scheduled for Monday. Hoping they will have a loaner car for me as promised.

hmmmm........comments/questions:

I've never had a spark plug "back out" on anything .......:iono:

Codes ...... have you checked with a code reader or just no codes showing on the dash .. ??

Are you going to drive the car between now and Monday ..... except to the dealer .. ??

Keep us posted.


humfrz

humfrz 01-03-2018 08:02 PM

1 Attachment(s)
Well, arren123, here's what you need ........ garrrrenteeed to fix whatever is ailing your car's engine .......:thumbsup:


humfrz

arren123 01-03-2018 08:44 PM

Quote:

Originally Posted by humfrz (Post 3023477)
hmmmm........comments/questions:

I've never had a spark plug "back out" on anything .......:iono:

Codes ...... have you checked with a code reader or just no codes showing on the dash .. ??

Are you going to drive the car between now and Monday ..... except to the dealer .. ??

Keep us posted.


humfrz

I've never had a spark plug back out either, but it was easy enough to check and hope for an easy fix.

I'm not driving the car between now and Monday. I'm getting it towed to the dealer since I still don't know the actual cause.

I just plugged in my Ecutek and used the DTC tool to verify there were no stored codes.

On the side note of doom and gloom..
There was a YouTube video I ran across where the guy had a rod/bearing issue. One of his comments "Ended up being a spun Rod 4 Bearing, apparently it wasn't out of the normal on the early first batch engines due to a front oil valley cover issue (passages too narrow or something along those lines). I got a replacement engine under warranty and it was fine ever since. The early engines have a #1 with an eagle looking logo stamped on the front cover, revised front covers have a #2 with no eagle. Sure they've done more revisions since then."

I looked at my cover and I found the eagle and I found the #1 on it :thumbdown:

humfrz 01-03-2018 09:35 PM

Quote:

Originally Posted by arren123 (Post 3023506)
.........................I looked at my cover and I found the eagle and I found the #1 on it :thumbdown:

What date was your car built ....??


humfrz


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