Startup stumble
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Teching In
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Startup stumble First, let me start with the fact I am brand new with HP Tuners. Engine is a 6.0 LQ4 with a Torquer V2 114 cam. When I start it it fires right up, then either almost stalls or does stall, then catches and runs and idles fine. What I see in the log when this happens is the spark advance dropping to -5 degrees, but I can't figure out what is causing that in the tune. Any help would be appreciative, and feel free to tell me how horrendous everything else is in the tune if you would like.
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From: Ann Arbor, MI
The problem is your spark tables have very low numbers in them, MUCH MUCH lower than even stock. Hotter cams typically support higher values.
Notice how the spark tables have g/sec on the vertical axis.
I see -5* in the 400 RPM column at .48 g/sec, which is probably where your engine stalls.
In contrast, the stock table has 14* in that location!
Replacing your idle and running spark tables with the stock values for a 2002 Camaro will make a huge improvement to your idle and even your power.
Read over the current tread:
https://ls1tech.com/forums/pcm-diagn...ng-stop-2.html
Compare yours to Jake's tune in post #28.
If you take his two idle spark tables, I'm confident your will have a perfect idle.
Then notice how he blended in the Idle Drive spark table into the main High Octane spark table so that there is no difference at low RPM, e.g. 1200 and below.
You could try his High Octane spark table, but I suspect it has too much advance near WOT settings.
Therefore I suggest:
1. Copy in Jake's Idle Drive and Idle Park tables.
2. Copy in the stock 2002 Camaro High Octane and Low Octane spark tables.
3. Copy Jake's 0, 400, 800 and 1200 columns to your High Octane spark table.
4. Learn how to tune the spark tables in the WOT sections.
Notice how the spark tables have g/sec on the vertical axis.
I see -5* in the 400 RPM column at .48 g/sec, which is probably where your engine stalls.
In contrast, the stock table has 14* in that location!
Replacing your idle and running spark tables with the stock values for a 2002 Camaro will make a huge improvement to your idle and even your power.
Read over the current tread:
https://ls1tech.com/forums/pcm-diagn...ng-stop-2.html
Compare yours to Jake's tune in post #28.
If you take his two idle spark tables, I'm confident your will have a perfect idle.
Then notice how he blended in the Idle Drive spark table into the main High Octane spark table so that there is no difference at low RPM, e.g. 1200 and below.
You could try his High Octane spark table, but I suspect it has too much advance near WOT settings.
Therefore I suggest:
1. Copy in Jake's Idle Drive and Idle Park tables.
2. Copy in the stock 2002 Camaro High Octane and Low Octane spark tables.
3. Copy Jake's 0, 400, 800 and 1200 columns to your High Octane spark table.
4. Learn how to tune the spark tables in the WOT sections.
Just take my idle tables from my last tune. They'll work awesome with your setup.
Then see how it works. I can walk you through tuning the idle. I just did it again today after I changed some things and had to retune.
Then see how it works. I can walk you through tuning the idle. I just did it again today after I changed some things and had to retune.
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Teching In
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*In Borat voice* Great success! I copied over the idle tables and the main spark tables, and she starts and idles much better. I have a dyno appointment next Saturday so I don't plan on flogging this poor POS till then. For the record this was a 4.8/5speed truck I swapped a spare LQ4 I had with a Torquer V2 cam into. Other than that, it's all stock. I'm not trying to race it, just want it to run well and do a few burnouts here and there.
My next question is, how do I interpret from my datalog what cell the VCM is looking at for timing? For example, right now it idles at 16 degrees of timing or so with a mass airflow of 11.7 g/sec according to the log but the tables are in cylinder air mass by grams. I don't know how to go from the log to the bin file and translate where the engine is running.
Thank you both for the help with idle and for helping me to learn HP Tuners.
My next question is, how do I interpret from my datalog what cell the VCM is looking at for timing? For example, right now it idles at 16 degrees of timing or so with a mass airflow of 11.7 g/sec according to the log but the tables are in cylinder air mass by grams. I don't know how to go from the log to the bin file and translate where the engine is running.
Thank you both for the help with idle and for helping me to learn HP Tuners.
When you're on throttle, it's pulling from the High Octane table unless you are in SD mode without a custom OS... then it's low.
As soon as you let off the gas and it goes to 0% TPS, it pulls from the idle tables. So idle are decel tables too.
As soon as you let off the gas and it goes to 0% TPS, it pulls from the idle tables. So idle are decel tables too.
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Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
...
My next question is, how do I interpret from my datalog what cell the VCM is looking at for timing? For example, right now it idles at 16 degrees of timing or so with a mass airflow of 11.7 g/sec according to the log but the tables are in cylinder air mass by grams. I don't know how to go from the log to the bin file and translate where the engine is running.
My next question is, how do I interpret from my datalog what cell the VCM is looking at for timing? For example, right now it idles at 16 degrees of timing or so with a mass airflow of 11.7 g/sec according to the log but the tables are in cylinder air mass by grams. I don't know how to go from the log to the bin file and translate where the engine is running.
You simply need to log "Cylinder Airmass" which has units of g/cyl. You
then know what row of the Spark table is being accessed. Remember there are adders and subtracters to the final spark advance value; some of us zero out those adders and subtracters (except for extreme temps) to simplify tuning.
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Verdad Gallardo That's a good practice without a Custom OS. Custom OS allows you to run Hi/Lo again.
But there's nothing that tells you it pulls from idle tables on decel. It actually doesn't grab a lower value in the main spark table. Which it seems like it should...
This is why it's important the idle and main spark tables match more or less.
But there's nothing that tells you it pulls from idle tables on decel. It actually doesn't grab a lower value in the main spark table. Which it seems like it should...
This is why it's important the idle and main spark tables match more or less.
Thread Starter
Teching In
Joined: Feb 2014
Posts: 49
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Thank you both for the help. The truck runs all around much better. Looking at the idle spark tables, does a manual transmission simply use the in park table or does it use the in drive table at some point?
I would make them match. I'm not sure if it pulls from park while in neutral and then when you go into first gear it switches. I'd have to log a 6-speed to see.
But for mine, I have my Park table lower than drive, since there is no load on the motor in park. And when I move to drive, I want there to be a spark "boost" to keep the motor happy since I have my idle set at 850 in both.
But for mine, I have my Park table lower than drive, since there is no load on the motor in park. And when I move to drive, I want there to be a spark "boost" to keep the motor happy since I have my idle set at 850 in both.
The manual transmission pretty much always uses the drive tables. Mine match, but that's how the tuner did them and I've had no reason to change it.
It might interface with the clutch and use the park tables with clutch in, but I can't confirm or deny that.
It might interface with the clutch and use the park tables with clutch in, but I can't confirm or deny that.