Spark Retard at lower coolant temps
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Car: 86 IROC
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Spark Retard at lower coolant temps
I have searched and have not been able to find what I am experiencing. When I first start my car and begin to drive with coolant temps around 30-50C, I get a lot of spark retard. Once the car reaches 70-80C all spark retard disappears. Full throttle, part throttle, idle.
Is there a table that adds spark to a cold motor to help warm it up quicker? If I am not mistaken there is one in $6E, as I had the same issue and was able to zero it out.
I am currently using $8D. Thanks
Is there a table that adds spark to a cold motor to help warm it up quicker? If I am not mistaken there is one in $6E, as I had the same issue and was able to zero it out.
I am currently using $8D. Thanks
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Re: Spark Retard at lower coolant temps
Thanks! Do you have the hack for $8D? What is the value at 8137?
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Re: Spark Retard at lower coolant temps
I was not able to find the hac? Do you know what directory it is within?
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Re: Spark Retard at lower coolant temps
At what point in the routine does it stop using that table to add spark? Once the ecm enters closed loop? Time delay?
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Re: Spark Retard at lower coolant temps
http://www.diy-efi.org/gmecm/papers/anht_hac.pdf
It is on this page:
http://www.diy-efi.org/gmecm/papers
RBob.
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Re: Spark Retard at lower coolant temps
Why not refer him to an updated hac?
There are known problems that have been updated.
http://www.gearhead-efi.com/gearhead...20and%20Hacks/
Look for AUJP_JP2.zip
There are known problems that have been updated.
http://www.gearhead-efi.com/gearhead...20and%20Hacks/
Look for AUJP_JP2.zip
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Re: Spark Retard at lower coolant temps
Why not refer him to an updated hac?
There are known problems that have been updated.
http://www.gearhead-efi.com/gearhead...20and%20Hacks/
Look for AUJP_JP2.zip
There are known problems that have been updated.
http://www.gearhead-efi.com/gearhead...20and%20Hacks/
Look for AUJP_JP2.zip
Yes, there are some errors in the original hac's, but they are better then nothing. I actually told that to someone that didn't like the ambiguities in my $61 hac. Flat out stated that if you don't like it, then do your own hac...
RBob.
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Re: Spark Retard at lower coolant temps
Why not refer him to an updated hac?
There are known problems that have been updated.
http://www.gearhead-efi.com/gearhead...20and%20Hacks/
Look for AUJP_JP2.zip
There are known problems that have been updated.
http://www.gearhead-efi.com/gearhead...20and%20Hacks/
Look for AUJP_JP2.zip
Looking at the hac, I cannot seem to understand how idle spark is calculated. My car will idle at 700-750rpm at op. temp, but in my logs the SA jumps all over the place. Looking at the tables none of the values make any sense. Can you run me through how idle spark advance is calc?
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Re: Spark Retard at lower coolant temps
possibly relevant, but assuming you remove the coolant temp dependant SA and still see KR, i've been in a few situations where even a slight misfire was being detected as knock. what would cause that at lower coolant temps and goes away at higher temps, i couldn't say, but just something to keep in mind.
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Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Re: Spark Retard at lower coolant temps
For anyone to spend the time it takes to even get close to detailing code, there are always be ommissions due to time or errors that "hopefully" the next guy will help adding detail to.
And for those that complain after they spent two hours looking over something you've worked on for a year and find an error...
I'm glad to see there are still some people who have taken the time to go over existing works and make them better.
Thanks to those who try and share.
Jp
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Re: Spark Retard at lower coolant temps
Thanks.
Looking at the hac, I cannot seem to understand how idle spark is calculated. My car will idle at 700-750rpm at op. temp, but in my logs the SA jumps all over the place. Looking at the tables none of the values make any sense. Can you run me through how idle spark advance is calc?
Looking at the hac, I cannot seem to understand how idle spark is calculated. My car will idle at 700-750rpm at op. temp, but in my logs the SA jumps all over the place. Looking at the tables none of the values make any sense. Can you run me through how idle spark advance is calc?
IIRC, $8D has a closed throttle SA table. So that will be used, then compensated for the idle RPM. Too high and the SA is decreased, too low and the SA is increased. Basically using torque control to smooth and prevent a rolling idle speed.
RBob.
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Re: Spark Retard at lower coolant temps
Yup,
For anyone to spend the time it takes to even get close to detailing code, there are always be ommissions due to time or errors that "hopefully" the next guy will help adding detail to.
And for those that complain after they spent two hours looking over something you've worked on for a year and find an error...
I'm glad to see there are still some people who have taken the time to go over existing works and make them better.
Thanks to those who try and share.
Jp
For anyone to spend the time it takes to even get close to detailing code, there are always be ommissions due to time or errors that "hopefully" the next guy will help adding detail to.
And for those that complain after they spent two hours looking over something you've worked on for a year and find an error...
I'm glad to see there are still some people who have taken the time to go over existing works and make them better.
Thanks to those who try and share.
Jp
RBob.
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Re: Spark Retard at lower coolant temps
I have searched and have not been able to find what I am experiencing. When I first start my car and begin to drive with coolant temps around 30-50C, I get a lot of spark retard. Once the car reaches 70-80C all spark retard disappears. Full throttle, part throttle, idle.
Is there a table that adds spark to a cold motor to help warm it up quicker? If I am not mistaken there is one in $6E, as I had the same issue and was able to zero it out.
I am currently using $8D. Thanks
Is there a table that adds spark to a cold motor to help warm it up quicker? If I am not mistaken there is one in $6E, as I had the same issue and was able to zero it out.
I am currently using $8D. Thanks
#18
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Car: 86 IROC
Engine: 350 Vortec TPI
Transmission: 700R4
Axle/Gears: BW 3.27
Re: Spark Retard at lower coolant temps
I lowered the value at L$031 from 40C to 20C and that helped.
I played around with the idle SA adv and retard last night by lowering the values in the first few cells. At idle the rpm would hunt a bit, but the biggest difference that I noticed was that when in gear and slowly accelerated the car did not jump forward. Prior to changing those values the car would feel sluggish and then jump forward.
Fast355 - Do you recall where that constant is or what it is called?
I played around with the idle SA adv and retard last night by lowering the values in the first few cells. At idle the rpm would hunt a bit, but the biggest difference that I noticed was that when in gear and slowly accelerated the car did not jump forward. Prior to changing those values the car would feel sluggish and then jump forward.
Fast355 - Do you recall where that constant is or what it is called?
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