Weird miss when I raise boost
#1
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Weird miss when I raise boost
Last weekend I adjusted my boost controller to give me a little more boost. I was running about 7-7.5 psi. I have a clocked Greddy w/ I/C and TEC3 ECU w/ 460cc injectors and a Hallman MBC.
The car has been running great, but then when I upped the boost slightly, as soon as it hits about 8 psi, it is like it loses spark. I thought the plugs may be gapped too far and adjusted them down to about .028 on the recommendation from a friend running a TEC2. I tried it again and the same problem existed. If you hold it to the floor it just goes through this bucking until it reaches about 4500 rpm then it will accelerate up to redline, possibly because it is back below 8 psi in that rpm range.
I took datalogs of the problem and it appears that my ignition advance goes to 0 right as the problem happens. I cannot see anything weird in my ignition or fuel tables that would cause this. Any ideas? When I drop the boost back to where I have been running, the problem is gone again.
The car has been running great, but then when I upped the boost slightly, as soon as it hits about 8 psi, it is like it loses spark. I thought the plugs may be gapped too far and adjusted them down to about .028 on the recommendation from a friend running a TEC2. I tried it again and the same problem existed. If you hold it to the floor it just goes through this bucking until it reaches about 4500 rpm then it will accelerate up to redline, possibly because it is back below 8 psi in that rpm range.
I took datalogs of the problem and it appears that my ignition advance goes to 0 right as the problem happens. I cannot see anything weird in my ignition or fuel tables that would cause this. Any ideas? When I drop the boost back to where I have been running, the problem is gone again.
#6
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I think I found it. There is an overboost fuel cut that I have active at 146 kpa! Didn't even know it existed. I will try it when I get home. Thanks for making me think. Sometimes all these extra enrichments and features are just more rope to hang yourself with.
#8
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i dont know if i ever ran over 8 psi on that unit
did you check the map sensor settings? it's a 2 bar unit I think.
edit: hung out in this thread too long that you posted your own solution :P
did you check the map sensor settings? it's a 2 bar unit I think.
edit: hung out in this thread too long that you posted your own solution :P
#9
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The boost cut was the problem. I was hitting about a 10 psi spike then it would taper off to about 8 psi. Do I need a helper spring on the Greddy wastegate actuator to combat that?
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Mikel
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09-28-2015 04:46 PM