AFR very very rich after bolt ons
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AFR very very rich after bolt ons
All,
I've added 2.5" upper and lower IC pipes, 3" intake, and 3" full exhaust. I've also added a Hallman pro MBC and a AEM wideband, boost gauges. NO Tune Yet! My car runs great, however its very very rich, so bad I smell fuel at WOT. When I have my boost set to 23psi peak, my AFR crusinig is ~12.5, but when the boost kicks in the AFR is <10. My wideband needle is buried.
I know I need a tune but I've never tuned a car before. If anyone has any recommendations about the following please help:
1. Tuning?
2. BOV?
3. Fuel Pump?
I've added 2.5" upper and lower IC pipes, 3" intake, and 3" full exhaust. I've also added a Hallman pro MBC and a AEM wideband, boost gauges. NO Tune Yet! My car runs great, however its very very rich, so bad I smell fuel at WOT. When I have my boost set to 23psi peak, my AFR crusinig is ~12.5, but when the boost kicks in the AFR is <10. My wideband needle is buried.
I know I need a tune but I've never tuned a car before. If anyone has any recommendations about the following please help:
1. Tuning?
2. BOV?
3. Fuel Pump?
Last edited by blu bi u; Mar 22, 2009 at 02:23 PM.
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The stock maps are made to go very rich when you increase the boost. This is to protect the engine by adding more fuel to lower combustion chamber temps. Seeing the AFR needle buried with the car boosting at 23psi is perfectly normal.
I see that you have an aftermarket intake, this will actually lean out your AFRs a little so if you had the stock intake, it'd probably be worse.
I see that you have an aftermarket intake, this will actually lean out your AFRs a little so if you had the stock intake, it'd probably be worse.
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I dont have any air or fuel leaks. I would expect the car to run leaner with an aftermarket intake. If I reduce the boost to 20psi peak then the wideband reads about 12 at WOT.
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The stock maps are made to go very rich when you increase the boost. This is to protect the engine by adding more fuel to lower combustion chamber temps. Seeing the AFR needle buried with the car boosting at 23psi is perfectly normal.
I see that you have an aftermarket intake, this will actually lean out your AFRs a little so if you had the stock intake, it'd probably be worse.
I see that you have an aftermarket intake, this will actually lean out your AFRs a little so if you had the stock intake, it'd probably be worse.
Can you see where my MAF sensor is. Do you think this is a "good" place for it?
Also, do you think bypassing the electronic boost control could have something to do with confusing the computer?
Thanks in advance
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With regards to the BOV...the stock one is perfectly fine, if you go aftermarket and vent to atmosphere you'll need to tune accordingly for it.
It shouldn't really lean the car out that much on the intake unless your intake uses a bigger MAF housing althought it will still lean it out somewhat by having an open element filter.
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Yes and no. 20 PSI is not all that much boost on this car and depending on timing you may be fine at 12:1 at only 20 PSI as long as you are adding more fuel as boost rises above that point. I agree that about 11.5:1 is usually optimal at peak boost but most guys run above that at least in the midrange. Up top everyone is running lower boost with the stock turbo sice it fades off.