Exhaust backfire after shift
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Exhaust backfire after shift
This is a problem that happens just about every time I shift after an agressive take off. Ever since I converted to SD, it has been doing it. I notice absolutely nothing in my diacom recordings that points to a possible cause. I have been having a problem with non PE accells when I hold in gear. For instance, start in first and slowly keep pushing the throttle to 45% or so and let the RPMS climb to 6000 about a 60-70 KPA areas. I have spots where where I'm too rich and my INT falls and then goes lean, car sputters and then recovers. This has really been hard to figure out. Anyone else ever had a similar problem to what I am describing? WOT the car is a beast.
Jason
Jason
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Car: An Ol Buick
Engine: Vsick
Transmission: Janis Tranny Yank Converter
<font face="Verdana, Arial" size="2">Originally posted by 89vette:
This is a problem that happens just about every time I shift after an agressive take off. Ever since I converted to SD, it has been doing it. I notice absolutely nothing in my diacom recordings that points to a possible cause. I have been having a problem with non PE accells when I hold in gear. For instance, start in first and slowly keep pushing the throttle to 45% or so and let the RPMS climb to 6000 about a 60-70 KPA areas. I have spots where where I'm too rich and my INT falls and then goes lean, car sputters and then recovers. This has really been hard to figure out. Anyone else ever had a similar problem to what I am describing? WOT the car is a beast.
Jason </font>
This is a problem that happens just about every time I shift after an agressive take off. Ever since I converted to SD, it has been doing it. I notice absolutely nothing in my diacom recordings that points to a possible cause. I have been having a problem with non PE accells when I hold in gear. For instance, start in first and slowly keep pushing the throttle to 45% or so and let the RPMS climb to 6000 about a 60-70 KPA areas. I have spots where where I'm too rich and my INT falls and then goes lean, car sputters and then recovers. This has really been hard to figure out. Anyone else ever had a similar problem to what I am describing? WOT the car is a beast.
Jason </font>
A real low back pressure exhaust tends to crackle. Might take a look at your DFCO stuff and see where your at, and try playing some with that.
Might try working with lowering your IAC counts.
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Jason,
I have the EXACT same problem. I am not real sure what is causing it. I have fooled with the IAC steps. Sometimes it does it, others it doesn't...?
Brendan
I have the EXACT same problem. I am not real sure what is causing it. I have fooled with the IAC steps. Sometimes it does it, others it doesn't...?
Brendan
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I have a manual car with and auto bin I started with. My IAC steps are about 20 at idle and vary as I drive. All the auto TCC stuff is shut off as well as EGR. I'm running a manual timing map. I'm running manual AE fuel tables with a 10% adder to the pump shot. I'm also running manual BLM cell boundrys for VE and RPM. I could plug my current timing and VE tables into the 90vette manual bin I have to see what happens I guess. Never really gave it much thought. With the MAF I never had the backfiring. If I can get this and the not so smooth non PE acells straighted out, I'll have a nice running car. Also on the non smooth acells, if I drop the PE enable to 30% it seems to cover it up. Are there any downfalls to lowering PE this low? Am I just covering up problem?
Jason
Jason
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