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Truck running rich with longtubes and EGR delete?

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Old Apr 4, 2011 | 05:47 AM
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Default Truck running rich with longtubes and EGR delete?

Finished my header install , and had to by pass my EGR , and I'm just wondering would this cause my truck to run rich? I am getting a srong smell of gas from exhaust ? Is this going to be normal from the new LT's ? What harm can be done? I know that if its to rich it can foul my plugs , but also I thought the EGR valve only opens at Idle ?Or could the smell be from the stainless headers breaking in ?
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Old Apr 4, 2011 | 06:13 AM
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yes its normal. you need a re-tune to lean out the fuel. Then the engine will make even more power.
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Old Apr 4, 2011 | 07:42 AM
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Originally Posted by JONeal
Finished my header install , and had to by pass my EGR , and I'm just wondering would this cause my truck to run rich? I am getting a srong smell of gas from exhaust ? Is this going to be normal from the new LT's ? What harm can be done? I know that if its to rich it can foul my plugs , but also I thought the EGR valve only opens at Idle ?Or could the smell be from the stainless headers breaking in ?
You need to turn off the EGR in the PCM. You can't just bypass it. The PCM will think something is wrong and add fuel to protect engine. When adding LT's, you would be lean if the emission's have been turned off in the PCM.
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Old Apr 4, 2011 | 09:58 AM
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You removed your cats when you installed the headers correct? This is the biggest contributor to the fuel smell that you're experiencing. The factory tune is actually fairly rich to help protect the engine, then the cats clean it up after that. Leaining out the mixture will definitely help and equal more power. As mentioned, a tune is necessary to account for the new found exhaust flow. I doubt that your plugs will foul out, the PCM should be able to adjust enough to keep that from happening.
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Old Apr 4, 2011 | 12:02 PM
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Correcto, plenty of room to adjust there. Also on a side note, an overly lean condition can smell very rich due to unburned hydrocarbons in the exhaust. If the mixture is too lean, the mixture is not densely populated with fuel molecules and as the mix fires off, the molecules are too far apart to comletely burn and you can be pumping fuel straight through. As mentioned though, a retune will hit the spot.
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Old Apr 4, 2011 | 05:48 PM
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Thanks guys !! Man yall good !!!
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Old Apr 5, 2011 | 01:45 PM
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Originally Posted by Rhino79
Correcto, plenty of room to adjust there. Also on a side note, an overly lean condition can smell very rich due to unburned hydrocarbons in the exhaust. If the mixture is too lean, the mixture is not densely populated with fuel molecules and as the mix fires off, the molecules are too far apart to comletely burn and you can be pumping fuel straight through. As mentioned though, a retune will hit the spot.
I believe that at that point the engine would be misfiring also
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Old Apr 5, 2011 | 08:00 PM
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I do too, just throwing out how a lean condition can "smell" rich.
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