Air to fuel ratio question

BLKBULLITT

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Yes fuck me I know but better safe than sorry and have the bitch blow...

07 gt d1 procharger intercooled system running 6psi has longtubes and offroad X...

Anyways idle it idles anywhere from 14.3-14.7
Cruising AFR is around 14.7
Now when in boost the numbers are basically the same as Normal driving?

Should I be worried that its running that lean?
 

LAStang1234

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Yes fuck me I know but better safe than sorry and have the bitch blow...

07 gt d1 procharger intercooled system running 6psi has longtubes and offroad X...

Anyways idle it idles anywhere from 14.3-14.7
Cruising AFR is around 14.7
Now when in boost the numbers are basically the same as Normal driving?

Should I be worried that its running that lean?


Those numbers are perfect for idling. Mine likes to hang around 14.3-15.3

Now when you've got your foot on the accelerator, say WOT what are the numbers showing? WOT you want your A2F to be around 11.3-11.5

Your afr is in the 14s when in boost?

Fixed! Lol
 
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BLKBULLITT

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Yes exactly it's around 14 while In boost. I imagine the gauge is accurate could anything be faulty or is it just tune related?

EDIT: that's while in WOT

Could the 02 sensor be bad? Because when at WOT it sort of stays perfectly around 14.7
 
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LAStang1234

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Yes exactly it's around 14 while In boost. I imagine the gauge is accurate could anything be faulty or is it just tune related?

EDIT: that's while in WOT

Could the 02 sensor be bad? Because when at WOT it sort of stays perfectly around 14.7

Definitely running lean then. Check the 02sensor that goes with the sensor. Have you tried asking the previous owner about it?
 

BLKBULLITT

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Yup just talked to him he thinks the gauge either shorted or a ground may be bad. Could also be a bad o2 sensor since I do have a CEL and the gauge stopped working when I met up with him.. Plugged it back in and started reading again. He says he saw 12s while under full boost.

Even he said if it was running 14s close to 15s under full boost the engine would of blown on him..
 

Alfiedagr8

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Double check it with a known good wideband if its really that lean. Monitor pids and see if there is a fault with the car or if it just needs a tune revision.


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Taxman

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Cobalt wideband

I had a problem with my cobalt reading wrong. My gauge read 14-15 all the time but when my shop hooked the car up to their sensor, it was 11 WOT. Sounds like a gauge issue.
 

Irishman

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Maybe the sensor needs to be calibrated due to it going out? Not sure about the cobalt but others you need to pull them out in the atmosphere and cycle them before installing in your exhaust.
 

ILW84U

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Looks like you may need my SOS dual A pillar & AEM A/F and boost guages. I would hope the A/F while at WOT is around 11.
 

TurboX

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While WOT, You want AF to be High 11-mid 12 depending on power level. Remember, Lean is mean but fat is safe.

While driving and under part throttle, even under boost you can run 14s or 15s.
 

AutoXRacer

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While WOT, You want AF to be High 11-mid 12 depending on power level. Remember, Lean is mean but fat is safe.

While driving and under part throttle, even under boost you can run 14s or 15s.

So in part throttle conditions its OK to be in the 14.0 range even if you have 1-10 PSI boost?
 

muztangman93

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I would imagine that would be safe. The boost guage itself could even be reading incorrectly I am not sure but if you were close to 15afr the car might even break up due to lack of fuel not sure if it would make a clean pull or not.
 

19COBRA93

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I had a wideband sensor fail and it read 14.7 almost all the time. I too think it's sensor/gauge related.

It should detonate every time with a 14.7 afr at full throttle under boost. Since it's not, that should be a good indication there's something else going on.
 
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