GReddy/XEDE 'stuttering' under boost
#1
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![Question](https://www.rx8club.com/images/icons/icon5.gif)
I've got a GReddy turbo with bigger secondary injectors and full control of timing, fuel, and boost via an XEDE.
Under ~6# of boost, I've noticed a bit of jerkiness and 'stuttering' under boost in higher gears (3-6)...more pronounced in the higher gears and at mid-RPMs. It runs smooth as butter when not in boost.
I'm running 2 gallons of 104 octane per tank of 91, so I don't think I'm pinging...I certainly don't hear anything.
Could this be a problem with the plugs or the coils? Any suggestions on how to diagnose it further?
Under ~6# of boost, I've noticed a bit of jerkiness and 'stuttering' under boost in higher gears (3-6)...more pronounced in the higher gears and at mid-RPMs. It runs smooth as butter when not in boost.
I'm running 2 gallons of 104 octane per tank of 91, so I don't think I'm pinging...I certainly don't hear anything.
Could this be a problem with the plugs or the coils? Any suggestions on how to diagnose it further?
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If it happens in low-mid rpm when you are in boost at higher gear, it may simply be that you are running too rich at that particular load and rpm. It happens to mine also, but mine is interceptor. Mine happens if I am at 3000 or lower rpm at 5th or 6th gear, going from vacuum to boost. Do you have wide-band, and do you know the a/f at that load & rpm?
#3
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If it happens in low-mid rpm when you are in boost at higher gear, it may simply be that you are running too rich at that particular load and rpm. It happens to mine also, but mine is interceptor. Mine happens if I am at 3000 or lower rpm at 5th or 6th gear, going from vacuum to boost. Do you have wide-band, and do you know the a/f at that load & rpm?
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I did both a dyno & street tune.
OK, so a wideband sounds like a good idea...once I have the cash to pay for it.
So, no guesses or potential diagnoses are forthcoming?
OK, so a wideband sounds like a good idea...once I have the cash to pay for it.
So, no guesses or potential diagnoses are forthcoming?
#8
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or it could be something as simple as a boost leak?
double check your vacuum lines and clamps, maybe air is leaking when the system is pressurized. or maybe there's a crack in a line. i've had a crappy vacuum line crack on me on my mr2 turbo at the external wastegate nipple, most likely from the heat.
double check your vacuum lines and clamps, maybe air is leaking when the system is pressurized. or maybe there's a crack in a line. i've had a crappy vacuum line crack on me on my mr2 turbo at the external wastegate nipple, most likely from the heat.
#9
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I will take your advice, and also compliment you on your avatars.
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