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Att tech's misfire issue bank to bank

TMac

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#21
No one called you a "punk", and you're right, I don't know anything about you- other than you're not willing to listen.

I know the very first thing I do when someone tries to help me is that I ignore their advice, become defensive, and reject anything that doesn't fit my own narrative about the problem. But, keep looking for that boost leak.
 

OP
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Thread Starter #22
anyways since I’m not listening lmao .
I didn’t see your pm until now. I’ve looked at the data posted and nothing really jumps out. The manifold absolute pressure is local baro plus boost, so you’re at about 15psi boost which is close to normal for stock tune. I’m thinking ignition timing, including any knock retard should be looked at as well.
As we speak the explorer has the bov an sct tune back in. Just so if that changes your views on the logs
An rear 02 seems to stay stuck an doesn’t bounce back fast enough. I’m gonna pull it an ohm it at that point I’ll check the cat
 

FORZDA3

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#23
anyways since I’m not listening lmao .


As we speak the explorer has the bov an sct tune back in. Just so if that changes your views on the logs
An rear 02 seems to stay stuck an doesn’t bounce back fast enough. I’m gonna pull it an ohm it at that point I’ll check the cat

Ok, but the rear O2s are narrow band and won’t read outside a small window. I don’t know the voltage conversion, but both sensors read the same in your log.
 

l1tech

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#24
The rear O2's are not going to switch if the cats are working properly. At a steady even cruise on flat ground they should read ~.750 mv and hardly move from there. If you go wot the rear O2s should read above .900 mv and on a full decel should drop to .100 mv and probably go to 0. The pcm is not going to consider anything the rear O2s have to say when you are wot, at a steady cruise is a different story but only slightly..

It is essential that a misfire profile relearn be performed and as of right now I know of no other way to do it other than with a scan tool which by the way has to be FDRS and you will need at least a VCM II. IDS has no support for the ST. If you have an active subscription to IDS then FDRS is a free download. It is different than IDS but if you are proficient with IDS you should have no issue figuring it out. If the misfire profile got skewed then it is very possible that the pcm may only think that there is a misfire and could be causing your issues. How is your drive belt and tensioner and the rest of the accessory pulleys/bearings? The pcm calculates misfires off of crankshaft speed and I have actually seen a drive belt that has coming loose due to a failed tensioner cause a false misfire code.

Another thing that I might do in this situation is to actually reprogram the pcm with Fords latest update just to eliminate the possibility that your info may have gotten corrupted. It sucks because you are going to get the auto ebrake (if that matters to you) but you would be surprised how many issues I have fixed by doing this
 

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Thread Starter #25
Okea guys a gals finally FORD found issue ! While the explorer had work done by them supposedly they found corrosion on the crank sensor. Which was causing the issue. Personally I think BS a they forgot something but either way it’s fixed a wanted to update if anyone else ends up with similar issues.
Thanks for all the help an inputs !!!!!
 

tylerhornsby1996

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#26
Okea guys a gals finally FORD found issue ! While the explorer had work done by them supposedly they found corrosion on the crank sensor. Which was causing the issue. Personally I think BS a they forgot something but either way it’s fixed a wanted to update if anyone else ends up with similar issues.
Thanks for all the help an inputs !!!!!
I’m actually having this issue now, we did a misfire correction , and I just had my long block replaced , any update on what the potential issue actually was?
 



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