Swapped L92 Random Lean Codes
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Joined: Dec 2017
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The O2 heaters AFAIK aren't under any kind of ECM control; they are powered off of the pink wire circuit. (hot whenever the key is On) I don't think a problem with that will show up in a data log, other than whatever you might see that would mean the sensors themselves aren't working right.
Yes I agree it's possible that a vacuum leak could cause all manner of problems. Usually they're worst at idle though; that's when vacuum is usually highest, i.e. when a leak will leak the most, as well as, when the amount of air flowing in the intake is lowest, meaning even a small amount of unmetered air can have a drastic effect. And speaking of unmetered air, how is your PCV system plumbed?
Yes I agree it's possible that a vacuum leak could cause all manner of problems. Usually they're worst at idle though; that's when vacuum is usually highest, i.e. when a leak will leak the most, as well as, when the amount of air flowing in the intake is lowest, meaning even a small amount of unmetered air can have a drastic effect. And speaking of unmetered air, how is your PCV system plumbed?
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Joined: Jul 2014
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From: OC, California
The O2 heaters AFAIK aren't under any kind of ECM control; they are powered off of the pink wire circuit. (hot whenever the key is On) I don't think a problem with that will show up in a data log, other than whatever you might see that would mean the sensors themselves aren't working right.
Yes I agree it's possible that a vacuum leak could cause all manner of problems. Usually they're worst at idle though; that's when vacuum is usually highest, i.e. when a leak will leak the most, as well as, when the amount of air flowing in the intake is lowest, meaning even a small amount of unmetered air can have a drastic effect. And speaking of unmetered air, how is your PCV system plumbed?
Yes I agree it's possible that a vacuum leak could cause all manner of problems. Usually they're worst at idle though; that's when vacuum is usually highest, i.e. when a leak will leak the most, as well as, when the amount of air flowing in the intake is lowest, meaning even a small amount of unmetered air can have a drastic effect. And speaking of unmetered air, how is your PCV system plumbed?
there is a live view of data you can see wit Hptuners I believe there is just a standard view that gives the info you would want to see. Sorry been a while since I have played with it, but you would want to see Maf readings, fuel trims, injector pulse, timing and o2 readings. this should give you a good idea of whats going on. you can also record this during a driving session so you can go back and look at the data assuming you dont see anything pop.
If your vac leak on your intake still didnt resolve the issue, id be curious to see the MAF readings, MAP sensor data could also tell you what Vacuum levels are which may point out another leak if thats your culprit
If your vac leak on your intake still didnt resolve the issue, id be curious to see the MAF readings, MAP sensor data could also tell you what Vacuum levels are which may point out another leak if thats your culprit
I had a heads cam C6z and that never had any idle issues warm or cold.. though that was tuned by my old tuner in Ohio who hasn't been responsive the past few months.
Last edited by Clegoat; Oct 30, 2020 at 04:18 PM.
