switched from OLSD to OLMAF only to have the same problem
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From: CroSSby, TexaSS
switched from OLSD to OLMAF only to have the same problem Hi guys, ive been steadily tuning my car the last couple of days. One of the reasons why I switched to open loop maf only was because I was told the maf wouldnt cause a lean idle condition on startup like it did with the SD tune... every hot start I do in open loop causes the car to go lean into the 20s and this isnt with a cold wideband either. Is this because of open loop? For the most part the maf is almost spot on. The problem is that closed loop throws everything out of whack and the afr bounces all over the place.
Things I've checked..
air is off
Car is indeed running maf only from 200rpm up.
02s are off. Temps set to 284 and disabled fuel trims
Things I've checked..
air is off
Car is indeed running maf only from 200rpm up.
02s are off. Temps set to 284 and disabled fuel trims
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From: CroSSby, TexaSS
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From: CroSSby, TexaSS
It's gone around 5 minutes just sitting there and it never went to commanded at idle even then on a hot start... so i just shut it off.. It's also stumbling at low steady take offs from a dead stop. Like miss fires, but i don't know whats going on. It doesn't do it once you get going though, i'll post up a log and my tune file.
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From: CroSSby, TexaSS
and here's how bad the Closed loop fuel trims differ from commanded AFR via Wideband. It causes an audiable difference in exhaust sound when the AFR swings or oscillates.
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From: CroSSby, TexaSS
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From: CroSSby, TexaSS
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From: CroSSby, TexaSS
This car has never run how i wanted it to.
Pretty much stuck/lost at this point lol
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From: CroSSby, TexaSS
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From: CroSSby, TexaSS
Here's two new files CTD, i got the IAC counts to mid 60's and i did a log, i also might have found the cure to my oscillation problem, the 02 switch points in the previous tune were different than a stock 6.0 so i added stock 6.0 02 switch points and the oscillation is less than before. while i was at it i changed my spark tables around, i got some knock at low rpms from a stand still take off just driving normal around town, That was not there before. how could i fix it?
I also want to fine tune the BRAF table, but i cannot do a cold start on the car, i have to hold the gas pedal down. would the russ k idle config help me any?
I also want to fine tune the BRAF table, but i cannot do a cold start on the car, i have to hold the gas pedal down. would the russ k idle config help me any?
More going on than the original post Huh! The link I sent do you remember reading this "do one change at a time" 
BRAF needs to be right, as does the start up airflow, rinse & repeat.
I'm guessing you are poking with stick & turning ***** not really understanding what the tables do & how they are going interact. As an example, why would you change the o2 switch points when you are in OL?
My suggestion would be go back to the stock file with correct injector data if you have changed them. Then start with basic's, start up airflow, rough in the BRAF, maybe increase the idle speed to stabilize. You don't have to leave the driveway! The guide is good starting point. Get it to start & idle properly
Then we can get back to the original post.
BRAF needs to be right, as does the start up airflow, rinse & repeat.
I'm guessing you are poking with stick & turning ***** not really understanding what the tables do & how they are going interact. As an example, why would you change the o2 switch points when you are in OL?
My suggestion would be go back to the stock file with correct injector data if you have changed them. Then start with basic's, start up airflow, rough in the BRAF, maybe increase the idle speed to stabilize. You don't have to leave the driveway! The guide is good starting point. Get it to start & idle properly
Then we can get back to the original post.
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From: CroSSby, TexaSS
More going on than the original post Huh! The link I sent do you remember reading this "do one change at a time"
BRAF needs to be right, as does the start up airflow, rinse & repeat.
I'm guessing you are poking with stick & turning ***** not really understanding what the tables do & how they are going interact. As an example, why would you change the o2 switch points when you are in OL?
My suggestion would be go back to the stock file with correct injector data if you have changed them. Then start with basic's, start up airflow, rough in the BRAF, maybe increase the idle speed to stabilize. You don't have to leave the driveway! The guide is good starting point. Get it to start & idle properly
Then we can get back to the original post.
BRAF needs to be right, as does the start up airflow, rinse & repeat.
I'm guessing you are poking with stick & turning ***** not really understanding what the tables do & how they are going interact. As an example, why would you change the o2 switch points when you are in OL?
My suggestion would be go back to the stock file with correct injector data if you have changed them. Then start with basic's, start up airflow, rough in the BRAF, maybe increase the idle speed to stabilize. You don't have to leave the driveway! The guide is good starting point. Get it to start & idle properly
Then we can get back to the original post.
I know what the fueling tables do. Its the idle tables that I know next to nothing about. I got the iac counts to mid 60s and the car felt like it wanted to start this morning so I must be getting closeIll look for a stock file so I can do the write up steps