frustered...
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From: Broken Arrow, OK
frustered... Ok, I have been working on my upper map 99Kpa to 200 (turbo car). Once I pass 100 to 105 Kpa the car falls apart. Timing is good and EQ 1.34 under boost. I have played with timing with no change. Fuel is e85, no knock recorded under boost.
It feels like a spark rev limiter..waaaaaa...blub blub blub. and all is ok when I let off. The BOV sounds and everything is cool. It does it worse under load like when boost builds before 3k. If I hold it in first till about 3000 and then hit it, it revs to 7000 quick with just a little protest. I thought I had bad fuel, but that is not the case. I thought I had some loose plug wires, but that is good too.
it is like somebody turns off a switch at 100 KPA.
injectors and fuel system great.
any thoughts??
It feels like a spark rev limiter..waaaaaa...blub blub blub. and all is ok when I let off. The BOV sounds and everything is cool. It does it worse under load like when boost builds before 3k. If I hold it in first till about 3000 and then hit it, it revs to 7000 quick with just a little protest. I thought I had bad fuel, but that is not the case. I thought I had some loose plug wires, but that is good too.
it is like somebody turns off a switch at 100 KPA.
injectors and fuel system great.
any thoughts??
When you say you played with your timing, what did you do? Are you absolutely positive you changed the timing in the area where it's occurring? I don't have EFI, but log your timing and see if you are getting the timing you are commanding. Also watch the log and see where on your timing map this is occurring and try reducing timing in that area. It is possible that you don't have the knock retard enablers turned on at this boost or RPM or something. You may be above your maximum brake torque timing in that area. Sometimes it won't report as knock since the sensors are piezo sensors and tuned to a small and specific range of frequencies. Bottom line is try reducing timing by 2-3° in that area and then smooth and blend that area and see how it does. If that doesn't work, take a few more. If you get no change whatsoever, your problem lies elsewhere. One other thing is cylinder pressure, i.e. boost does its best to put out spark, so if you don't have good voltage, due to a bad coil or ground, that will cause it. Also, no platinum plugs. Use TR6's and gap them to .030"-.035". I run .035". The only way to check plug wires is with a good meter. Meter them and look for the odd man out. My MSD wires when good are always around 25 ohm. Let me know what you find.
Last edited by BLOWNBLUEZ06; Oct 16, 2009 at 03:52 AM.
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When you say you played with your timing, what did you do? Are you absolutely positive you changed the timing in the area where it's occurring? I don't have EFI, but log your timing and see if you are getting the timing you are commanding. Also watch the log and see where on your timing map this is occurring and try reducing timing in that area. It is possible that you don't have the knock retard enablers turned on at this boost or RPM or something. You may be above your maximum brake torque timing in that area. Sometimes it won't report as knock since the sensors are piezo sensors and tuned to a small and specific range of frequencies. Bottom line is try reducing timing by 2-3° in that area and then smooth and blend that area and see how it does. If that doesn't work, take a few more. If you get no change whatsoever, your problem lies elsewhere. One other thing is cylinder pressure, i.e. boost does its best to put out spark, so if you don't have good voltage, due to a bad coil or ground, that will cause it. Also, no platinum plugs. Use TR6's and gap them to .030"-.035". I run .035". The only way to check plug wires is with a good meter. Meter them and look for the odd man out. My MSD wires when good are always around 25 ohm. Let me know what you find.
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PissedThis does not happen to me
. My car needs Viagra.I tried 19 deg and boost all the way up to 29 deg. Still no change.
2800 stall, car makes boost at about 2700. In first gear at about 2000rpm I can nail it and it will go on into boost with juust a hint of miss. Once I let it shift into second.... lights out baw.baw.baw... sounds like it is in the intake, nothing backfiring out the exhaust. If I let it shift into second and then roll into it, lights out... sounds like a pre-stage limiter set to low and then it just quits until I let it fall below 105 kpa. Is it on boost too soon? Fuel pressure good and cylinder balance is even.
EQ 1.3 under boost... by the gauge
Help please.. this is impacting my sex life
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did a cylinder balance last night... everything good. checked gap again... .035 I thought it was .30. plug wires 27 ohm. I am begining to think this is not the tune at all, but something under the hood like blownbluezo6 said.
edit:Ground shows good to body and coil packs.
edit:Ground shows good to body and coil packs.
Last edited by Tzion_ben_Arthur; Oct 17, 2009 at 10:59 AM.
It sounds to me like you are blowing your spark out. Ive been down this road before, and unfortunately I had to buy the LS2 round truck coils for the problem to disappear. Try gapping your plugs down to .022-.025 to see if that helps. Before I bought the new coils, mine was actually gapped at .018 and still missing like you describe. They are gapped at .025 now with the new coils and no miss.
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It sounds to me like you are blowing your spark out. Ive been down this road before, and unfortunately I had to buy the LS2 round truck coils for the problem to disappear. Try gapping your plugs down to .022-.025 to see if that helps. Before I bought the new coils, mine was actually gapped at .018 and still missing like you describe. They are gapped at .025 now with the new coils and no miss.
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Update!!!!
put plugs at .028 with new wires, same deal. Took out the e85 and put petro back in with a gas tune and all is good now. From the best I can tell the e85 sat in the tanks so long that it soaked up water. I am now doing some WOT data runs at 6psi this week and will bump up to 10 psi next week.
put plugs at .028 with new wires, same deal. Took out the e85 and put petro back in with a gas tune and all is good now. From the best I can tell the e85 sat in the tanks so long that it soaked up water. I am now doing some WOT data runs at 6psi this week and will bump up to 10 psi next week.
