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Im experiencing spark blow out at 5700 rpm and 10 psi from a greddy 18g
Looking at my logs it shows my battery voltage dropping from 13.4 to about 12.3
I had my gap at 28 then 24 and finally down to 20 and that is when the blow out has stopped.
Havent taken it all the way to redline yet (7000 rpm)
Will this small voltage drop be the reason why im getting this blow out at such low rpm and boost?
The motor is a high comp b20b with phk pistons (comp test shows 270psi across all four)
Gsr head
Aemv2
Kcoils
Aem epm
Greddy 18g
7 heat range ngk resistor plugs in
If this voltage drop im experiencing is the problem how do i go about troubleshooting? Is it almost always the voltage regulator in the alternator?
You're voltage drop is causing this issue. Its not having enough voltage to jump the gap, which is the reason closing the gap, is bandaiding the issue right now.
Figure out your voltage drop, in all reality, you should be at 13.8+ Volts while driving, in a honda, some cars are higher, at work, our alt put out 14.6+ volts at idle.
I would venture to say, figure out voltage issue first, more then likely, its a ATL, once its replaced, open your gap back up and see how that works. Although the stock ign should be good for 500-600whp, sometimes, you may not be able to experience what everyone else, is doing. Every motor is different, depending on plugs, wires and coil used, you could be limited.. You're on AEM though, i dont think you'll have any issues, but a low voltage will hinder your coil voltage.
You're voltage drop is causing this issue. Its not having enough voltage to jump the gap, which is the reason closing the gap, is bandaiding the issue right now.
Figure out your voltage drop, in all reality, you should be at 13.8+ Volts while driving, in a honda, some cars are higher, at work, our alt put out 14.6+ volts at idle.
I would venture to say, figure out voltage issue first, more then likely, its a ATL, once its replaced, open your gap back up and see how that works. Although the stock ign should be good for 500-600whp, sometimes, you may not be able to experience what everyone else, is doing. Every motor is different, depending on plugs, wires and coil used, you could be limited.. You're on AEM though, i dont think you'll have any issues, but a low voltage will hinder your coil voltage.
I had the same issue with my last project using a fresh C5 enging boosted with a ATI Pro charger using a brand new AEM V2 unit and full AEM COP conversion, had ignition break up at 6psi, then one of the coils went out during the dyno good thing i had a OEM honda disributor set on the side. I sold the enire unit only to find out the AEM ECU gave out later down the road for some reason, i never really had good experiences with AEM products. Not that this helps only to tell you your not alone.
That and the aem EPM is known for having issues. Get the voltage drop squared away first if still having issues you'll need to address the trigger system. T1 and dont look back
You're voltage drop is causing this issue. Its not having enough voltage to jump the gap, which is the reason closing the gap, is bandaiding the issue right now. Figure out your voltage drop, in all reality, you should be at 13.8+ Volts while driving, in a honda, some cars are higher, at work, our alt put out 14.6+ volts at idle. I would venture to say, figure out voltage issue first, more then likely, its a ATL, once its replaced, open your gap back up and see how that works. Although the stock ign should be good for 500-600whp, sometimes, you may not be able to experience what everyone else, is doing. Every motor is different, depending on plugs, wires and coil used, you could be limited.. You're on AEM though, i dont think you'll have any issues, but a low voltage will hinder your coil voltage.
Thanks for the advice. Ill be swapping out the alt today and open the gap up and see if that fixes it
That and the aem EPM is known for having issues. Get the voltage drop squared away first if still having issues you'll need to address the trigger system. T1 and dont look back
I had the same issue with my last project using a fresh C5 enging boosted with a ATI Pro charger using a brand new AEM V2 unit and full AEM COP conversion, had ignition break up at 6psi, then one of the coils went out during the dyno good thing i had a OEM honda disributor set on the side. I sold the enire unit only to find out the AEM ECU gave out later down the road for some reason, i never really had good experiences with AEM products. Not that this helps only to tell you your not alone.
to be honest im not sure but i think they would because that was the case when i sent them the bad coil they tested it and sent me a new one but i still had to pay a few bucks for them to test it!
If battery has a dead cell it'll cause excessive draw on the charging system but I imagine you would see that regardless of rpm. You have good grounds?
Alternator should be outputting no more than like 14-15 volts when the motor is running. Use a multimeter to measure alternator output voltage at idle.
It's more than likely the regulator like I said. Do you have a spare alternator you could swap?
Swapped the alternator and still getting a voltage drop as the rpms rise. I didn't do a full pass as I let off and just brought the car home I didn't open my cutout that's why the af ratio is soo rich
Originally Posted by wantboost
Alternator should be outputting no more than like 14-15 volts when the motor is running. Use a multimeter to measure alternator output voltage at idle. It's more than likely the regulator like I said. Do you have a spare alternator you could swap?
If battery has a dead cell it'll cause excessive draw on the charging system but I imagine you would see that regardless of rpm. You have good grounds?
I have the tranny ground no valve cover ground
Never had a problem for the last 3 years like this
My next step today is adding another ground to the valve cover
With my meter probing all over the motor to chassis i get 0 resistance so it should be fine but im gonna add that valve cover ground and double check
There is a harness ground as well on the thermostat housing ensure its clean it feeds the ecu. Many people forget about this one, forget to put it on once and go crazy because the car wont start and you wont ever again. lol
There is a harness ground as well on the thermostat housing ensure its clean it feeds the ecu. Many people forget about this one, forget to put it on once and go crazy because the car wont start and you wont ever again. lol
I'm not saying it is but you need to be careful where things are grounded they are put in a place for a reason. Improperly grounded locations can lead to ground loops and electrical noise. Just like too many grounds can cause problems as well.
I'm not saying it is but you need to be careful where things are grounded they are put in a place for a reason. Improperly grounded locations can lead to ground loops and electrical noise. Just like too many grounds can cause problems as well.
I know sensor grounds are meant to be all together
As for other grounds for 12v higher current sensors it shouldn't matter its all grounded to the chassis
The ground is inside the cabin where the stock ecu would mount. Never had spark issues before this.
Originally Posted by DDTECH
Met's got a point.. where's your current ground locations right now? Did your old ATL test bad??
I have a bunch of spares from old motors i just swapped it really quick
I didnt get a chance to mess with the car today ill update tomorrow
Are you relying solely on what the ecu displays to monitor system voltage? You might try an external voltage gauge or multimeter as a second source. Hook either directly to the battery and monitor and compare that reading to what the ecu says. Should help you determine if it's an ecu problem or a wiring/ground problem.
Also I would try and monitor the amp load while doing a pull. It could help you locate a system out component that's experiencing excess current draw leading to a voltage drop.
Are you relying solely on what the ecu displays to monitor system voltage? You might try an external voltage gauge or multimeter as a second source. Hook either directly to the battery and monitor and compare that reading to what the ecu says. Should help you determine if it's an ecu problem or a wiring/ground problem. Also I would try and monitor the amp load while doing a pull. It could help you locate a system out component that's experiencing excess current draw leading to a voltage drop. Just my opinion
Hmmmm ill try that.
That should rule out the ecu.
Im also gonna try and get rid of the alternator control from the ems and just leave the positive control cable
01-04-2015, 11:10 AM
Ignition breakup (aemv2, k coils, epm)
