Random misfire at high RPM - thanks to anyone in advance for any info
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CL65 AMG , white S550 Sport w/ white Giovanna 22s, wild custom chopper
Random misfire at high RPM - thanks to anyone in advance for any info
Here is some history on the car, prior to the misfires.
2013 - install Speedriven ECU/TCU tune, no issues
2015 - install Speedriven Intercoolers with new tune - no issues
mid 2016 - late night got random misfire, CEL flashing while nder acceleration on the freeway, restart car and all ok
late 2016 - condition repeated itself a few times rarely
late 2016 - passenger coil pack completely fails, car doesn't start, engine codes say misfire on all passenger side cylinders, entire bank is gone
late 2016 - passenger side coil pack is rebuilt by v12icpack folks http://www.v12icpack.com/ - car immediately starts up with new coil pack. at this point I assume that was root cause of all my misfires
early 2017 - while engine is suspended for a broken motormount replacement, turbos are upgrade with the Speedriven rebuilt set with light weight impeller, catless downpipes with rear O2 sensors plugged into some de-faulers, new ECU tune from Speedriven for the new turbos.
after this, the problem becomes very repeatable very easy to simulate everytime high RPM is hit.
Any ideas on how to troubleshoot this? Including some pictures of data log, freeze frame and engine codes.
2013 - install Speedriven ECU/TCU tune, no issues
2015 - install Speedriven Intercoolers with new tune - no issues
mid 2016 - late night got random misfire, CEL flashing while nder acceleration on the freeway, restart car and all ok
late 2016 - condition repeated itself a few times rarely
late 2016 - passenger coil pack completely fails, car doesn't start, engine codes say misfire on all passenger side cylinders, entire bank is gone
late 2016 - passenger side coil pack is rebuilt by v12icpack folks http://www.v12icpack.com/ - car immediately starts up with new coil pack. at this point I assume that was root cause of all my misfires
early 2017 - while engine is suspended for a broken motormount replacement, turbos are upgrade with the Speedriven rebuilt set with light weight impeller, catless downpipes with rear O2 sensors plugged into some de-faulers, new ECU tune from Speedriven for the new turbos.
after this, the problem becomes very repeatable very easy to simulate everytime high RPM is hit.
Any ideas on how to troubleshoot this? Including some pictures of data log, freeze frame and engine codes.
#2
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CL65 AMG , white S550 Sport w/ white Giovanna 22s, wild custom chopper
Update as of this AM - now it's always following cylinders 7 & 9, and it's happening at low RPM, tripped it at around 600 rpm twice this morning.
#3
If it repeats itself over and over since the turbo, it's the POS turbos Speedriven sold you is causing excessive preturbine back pressure. Easy way to find out if this is the cause is to loosen your waste gate rods way off. Like no preload and see what happens.
Could also be spark blow out, plugs, boots, coil not that healthy. But I'm assuming you've checked all that.
Could also be spark blow out, plugs, boots, coil not that healthy. But I'm assuming you've checked all that.
#4
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CL65 AMG , white S550 Sport w/ white Giovanna 22s, wild custom chopper
This is occurred before the turbo upgrade, but was very rare. Should I be at very high boost if my wastegates are working? I don't see above 20 using the OBDII apps. Manual gauge showed a spike at 20.5.
If it repeats itself over and over since the turbo, it's the POS turbos Speedriven sold you is causing excessive preturbine back pressure. Easy way to find out if this is the cause is to loosen your waste gate rods way off. Like no preload and see what happens.
Could also be spark blow out, plugs, boots, coil not that healthy. But I'm assuming you've checked all that.
Could also be spark blow out, plugs, boots, coil not that healthy. But I'm assuming you've checked all that.
#5
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I'm getting PO Codes P309,P312 from a coil I never replaced, Driver side.
It's just starting, rare right now but I know how it degrades since I had a similar experience with the Passenger side Coil pack, that one got replaced.
I'm thinking of using the v12icpack folks and getting two rebuilt ones for the price of getting one brand new coil pack, so their installs are synced... maybe they can make it extra heavy duty somehow for tuned cars.
Did you get new red boots when you got the passenger side one from them?
It's just starting, rare right now but I know how it degrades since I had a similar experience with the Passenger side Coil pack, that one got replaced.
I'm thinking of using the v12icpack folks and getting two rebuilt ones for the price of getting one brand new coil pack, so their installs are synced... maybe they can make it extra heavy duty somehow for tuned cars.
Did you get new red boots when you got the passenger side one from them?
Last edited by NRL; 08-31-2017 at 07:09 PM.
#6
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CL65 AMG , white S550 Sport w/ white Giovanna 22s, wild custom chopper
I'm getting PO Codes P309,P312 from a coil I never replaced, Driver side.
It's just starting, rare right now but I know how it degrades since I had a similar experience with the Passenger side Coil pack, that one got replaced.
I'm thinking of using the v12icpack folks and getting two rebuilt ones for the price of getting one brand new coil pack, so their installs are synced... maybe they can make it extra heavy duty somehow for tuned cars.
Did you get new red boots when you got the passenger side one from them?
It's just starting, rare right now but I know how it degrades since I had a similar experience with the Passenger side Coil pack, that one got replaced.
I'm thinking of using the v12icpack folks and getting two rebuilt ones for the price of getting one brand new coil pack, so their installs are synced... maybe they can make it extra heavy duty somehow for tuned cars.
Did you get new red boots when you got the passenger side one from them?