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Mods :
Inline Pro Turbo Kit with SC5865
NGK 7446 Spark Plugs
18psi
Hondata FlashPro
As the weather started getting a bit warmer, my car began breaking up around 6k rpms. It didn't feel to be getting any slower, just loud popping out of the exhaust. After a lot of trial and error, I lowered the gap of the NGK 7446 Spark Plugs from .035' to .030'. That helped, quite a bit with the popping not starting until 7k rpms.
The next day I changed the gap down to .027'. The popping/breaking up was completely gone.
Now.. on hot days my car has trouble starting. It continues to attempt to crank, probably 5-7 seconds. Sometimes after that it will start, but immediately stall unless I smack the gas to rev it up right as it starts.
I've lowered Cranking Fuel Trim from 3% (original tune) to 0%, still did it. Then lowered it to -4%. It was fine the other day when it was 85' outside, but yesterday when it was 100' it wouldn't start.
Last night I tried lowering it to -8% (approximately 85' out).. but it wouldn't start at all.
Working with my tuner to resolve it, but it's a pain since he's three hours away.
All your work will be done in on the last screen you posted - "Air Temp Fuel Comp" Cranking. During cranking the ECU reads the IAT and references that table for how much fuel to add/subtract. As you can see, for warm starts there is hardly any resolution (134-224). You'll need to play with this table to get this working correctly.
Pull the datalog you posted back up and graph IAT. Stick your cursor inside the datalog where the IAT is highest and go back to the temp comp screen. A highlighted box will be lit for the corresponding temp (it is going to be a correlated value in the table since the resolution is so low). You have two choices - you can more relevant breakpoints in the table for the temps your car will actually be seeing or just play with the values in the 3 far right boxes (all depending on what your actual IAT is). Your location isn't in your profile, but I'm going to go out on a limb and say you'll need to pull more fuel out. Reset your cranking trim back to zero so the two compensations aren't fighting each other.
Originally Posted by spectacle,Jul 6 2010, 12:54 PM
Ok here is what you need to do.
All your work will be done in on the last screen you posted - "Air Temp Fuel Comp" Cranking. During cranking the ECU reads the IAT and references that table for how much fuel to add/subtract. As you can see, for warm starts there is hardly any resolution (134-224). You'll need to play with this table to get this working correctly.
Pull the datalog you posted back up and graph IAT. Stick your cursor inside the datalog where the IAT is highest and go back to the temp comp screen. A highlighted box will be lit for the corresponding temp (it is going to be a correlated value in the table since the resolution is so low). You have two choices - you can more relevant breakpoints in the table for the temps your car will actually be seeing or just play with the values in the 3 far right boxes (all depending on what your actual IAT is). Your location isn't in your profile, but I'm going to go out on a limb and say you'll need to pull more fuel out. Reset your cranking trim back to zero so the two compensations aren't fighting each other.
Hope that makes sense.
That actually helps, a lot! The hottest temperature that it sees is 116.8' F.
Located in Virginia Beach, VA... so it definitely gets rather toasty. Yesterday evening the IAT was reading around 150' F... even more tough time starting.
I'm rather new to this, so not sure the best way to go about adding in more breaking points into the table for additional temperatures... and then choosing what value I should use for those.
You'll never see a 200d IAT so that's pretty much a rediculous breakpoint. I would start with changing the last 3 breakpoints to 95 - 125 - 155 & the trims to -1% -3% & -5%, respectively. You'll have to play with it to get things just right...just a bunch of trial and error.
So anytime I go to start the car now, just plug in the EMS and keep an eye on IAT? If it has troubles starting, pull more fuel in half degree increments and see how she does?
07-06-2010, 05:47 AM
Trouble Starting on Hot Days
