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Stuttering when I shift at high rpm

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Oromocto
#1
I installed my Cobb rear motor mount and access port and the weekend after I noticed when I go wide open throttle until 5500rpm or more, then shift and go right back to wide open, my car studders, usually 3 quick “duhduhduh” then carries on normal, it’s most noticeable in 4th-6th gears when I shift at 5500+rpm, any ideas?? Car has 100k kms
 


kivnul

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Deer Park, WA
#2
Info that might help others to diagnose this:

Current car modifications:
Which tune you are running:

Have you tried going back to either the true stock tune or cobbs stage 0 tune to see if it still does it?
 


OP
T
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Oromocto
Thread Starter #3
Current mods: COBB RMM, Injen Intake, Boomba Bov adaptor, MBRP exhaust, AP with custom tune from JSTPerformance, happened with Cobb stage 1, and I haven’t tried putting the stock tune as I haven’t thought until now to do that, but now that you mention I went Cobb stage 1 the same time I did my RMM and noticed the problem that following weekend
 


OP
T
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Oromocto
Thread Starter #4
Thank you I have added that information, have not tried stock/stage 0 tune I’ll do that as soon as I get i get home, I’m wondering if it’s dirty injectors or a problem with blow by stopping my valve seal? I have over 100k, have never cleaned it with that crc gdi spray, and don’t have a catch can
 


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Location
Portland
#5
Can you take a video of the issue?
I'm at roughly the same mileage and my bolt ons are pretty similar, yet I don't have this issue.
 


OP
T
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Location
Oromocto
Thread Starter #6
[MENTION=4809]LaserWhisperer[/MENTION] I will take a video as soon as I get home, I don’t get home until the 3rd, I also am not sure I’ll be able to capture the sound where it’s not extremely loud but I’ll do my best to show what’s happening
 


OP
T
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Oromocto
Thread Starter #8
I thought about getting driver and passenger mounts to see if that would fix it, how are you sure it’s passenger and not driver? Just curious as to why you say that side, thanks in advance
 


LaserWhisperer

Active member
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Location
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#10
I thought about getting driver and passenger mounts to see if that would fix it, how are you sure it’s passenger and not driver? Just curious as to why you say that side, thanks in advance
Open the hood, grab and shake the engine near the passenger side mount and listen for squeaks. It'll be quite loud if it's bad. I recently installed the powerflex mounts on both sides, what a difference!
 


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