Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post

nlowell · 06-26-2016, 12:21 AM

{See below for the fix}

[Background]
I have a challenge for the group that is driving me nuts.

2013 Automatic Scion FRS with KW C30 SC and other accompanied upgrades. I developed a metal knocking noise that can be definitively heard with a stethoscope on the passenger head. It's erratic in rhythm.

{I also had issues stalling on startup that I didn't know were related until I found the fix below}

So I decided to have my engine rebuilt - chose Outfront Motorsports as they are Subaru rebuilding experts with FRS experience.

They pulled the engine and while they found some scoring on the bearings - they didn't find anything in the heads that would be causing the knocking.

I had the whole thing rebuilt - forged pistons (custom stock compression CP) and rods (turbo tuff), new stock bearings, machined heads, new Ferrea valves, new double springs, titanium retainers and even new rockers just to be safe.

I don't drive the car all that much and have only put 2-3k miles on the new engine with no track time and a few oils changes for good measure.

Well - the damn knock is still there...

Hate to pay to pull the engine again as they didn't find anything the first time.

Even more so, hate to buy new heads as I've already paid for mine to have all of the upgrades.

Any thoughts?

https://vimeo.com/172263792

[Confirmed Fix!]
Automatics have a special vacuum pump that is attached to the cam (instead of just a cover) on the passenger rear of the engine. This pump had gone bad causing stalling issues AND the metal knocking. Since it is attached to the cam, it was masking itself as potential rocker noise. Pump, O-ring and gasket maker was $170. Install was 20 minutes taking my sweat time. Fix is confirmed! She purrs like a kitten with no stalls or clanking noises! I've been chasing this over a year and have spent $12k in upgrades trying to get rid of it. Hopefully others can shortcut this

06-26-2016, 12:21 AM	#1
nlowell Senior Member Join Date: May 2013 Drives: 2013 Scion FRS Location: Dallas, TX Posts: 443 Thanks: 105 Thanked 409 Times in 173 Posts Mentioned: 51 Post(s) Tagged: 0 Thread(s)	Metal knock {See below for the fix} [Background] I have a challenge for the group that is driving me nuts. 2013 Automatic Scion FRS with KW C30 SC and other accompanied upgrades. I developed a metal knocking noise that can be definitively heard with a stethoscope on the passenger head. It's erratic in rhythm. {I also had issues stalling on startup that I didn't know were related until I found the fix below} So I decided to have my engine rebuilt - chose Outfront Motorsports as they are Subaru rebuilding experts with FRS experience. They pulled the engine and while they found some scoring on the bearings - they didn't find anything in the heads that would be causing the knocking. I had the whole thing rebuilt - forged pistons (custom stock compression CP) and rods (turbo tuff), new stock bearings, machined heads, new Ferrea valves, new double springs, titanium retainers and even new rockers just to be safe. I don't drive the car all that much and have only put 2-3k miles on the new engine with no track time and a few oils changes for good measure. Well - the damn knock is still there... Hate to pay to pull the engine again as they didn't find anything the first time. Even more so, hate to buy new heads as I've already paid for mine to have all of the upgrades. Any thoughts? https://vimeo.com/172263792 [Confirmed Fix!] Automatics have a special vacuum pump that is attached to the cam (instead of just a cover) on the passenger rear of the engine. This pump had gone bad causing stalling issues AND the metal knocking. Since it is attached to the cam, it was masking itself as potential rocker noise. Pump, O-ring and gasket maker was $170. Install was 20 minutes taking my sweat time. Fix is confirmed! She purrs like a kitten with no stalls or clanking noises! I've been chasing this over a year and have spent $12k in upgrades trying to get rid of it. Hopefully others can shortcut this __________________ Complete Part Out: http://www.ft86club.com/forums/showthread.php?t=125688 Last edited by nlowell; 06-29-2016 at 05:55 PM.