BOGGING BADLY! - SOLVED

I got a good look at the 3rdcat and it looks very clear.. Did NOT chevk primaries, but the 02 sensor data looks good? (Secondary o2's mirror primary o2s instantly)

This should be it. Must have broken it putting it back in? I inspected all the plugs/ceramics before.. hmmm.
I also did drop one plug removing them, but that was #8, not #2..


Will update once I get a new plug (of course I have 3 boxes full of old parts but I pitched the old plugs)
Thing is, I looked at an earlier log. No misfires even while it was knocking/bogging.. This maybe a separate issue I just created, and may have nothing to do with the bog!

J91z is correct in the loading being off on that hp tuners scan. You will never be able to hit .56 grams per cylinder at 2 thousand rpms under normal conditions unless you have a trailer behind you and floor it from a dead stop. It isn't false knock because it is going right into a load range that shouldn't be attainable. Your trans is either stuck in a gear it shouldn't be, your converter is piled up (but that would have it idling like shit in drive trying to push against your brakes) or your fuel pressure is dropping off. I would log fuel pressure, I bet it is dropping off hard when you floor it.

Sorry, missed you logged fuel pressure. It's 43 when you hit it, what does it do as you went further into the log?

Fuel pressure solid at 43!

Ha! I missed the last post with the broken plug. That should be it, but if not, I will build you a custom scan profile with everything needed to nail it down. Your logs no matter what you are doing, should always have current misfires 1 through 8 no matter what you are doing. It would have shown that plug problem.

EXCEPT, I have a previous log before I pulled the plugs and it has a "total misfires" count. Only lit up a couple misfires here and there, not missing when the knock retard is going. Currently it misses a ton, going to get that plug now..

Thanks for the help, I may need that scanner profile yet!

mikez71 said:

EXCEPT, I have a previous log before I pulled the plugs and it has a "total misfires" count. Only lit up a couple misfires here and there, not missing when the knock retard is going. Currently it misses a ton, going to get that plug now..

Thanks for the help, I may need that scanner profile yet!

Click to expand...

I have been tuning since ls1 edit in 1998 and have over 4 thousand tunes on hp tuners alone. I have a really good idea of what to scan to nail it down if needed. See how the plugs go

No more misfires! STILL bogs, still knock retards. I was watching the Tech2, and individual cylinder knock rarely came up, when it did, they all lit up.
But even without individual cylinder knock, there was still knock retard.? (Unless it happened so fast I missed it)
Engine back to being smooth, but still not right coming off the line..

How to test knock sensors? Or should I just unplug them to test? or de-sensitize them in tune?
Other than that I will take a look at everything around the engine that could be rattling..

Thanks all for your patience and help!

mikez71 said:

No more misfires! STILL bogs, still knock retards. I was watching the Tech2, and individual cylinder knock rarely came up, when it did, they all lit up.
But even without individual cylinder knock, there was still knock retard.? (Unless it happened so fast I missed it)
Engine back to being smooth, but still not right coming off the line..

How to test knock sensors? Or should I just unplug them to test? or de-sensitize them in tune?
Other than that I will take a look at everything around the engine that could be rattling..

Thanks all for your patience and help!

Click to expand...

It isn't your knock sensors. Is it still loading to .56 grams per cylinder when you get into it?

Yep! .6 grams per cylinder! here is a log file in post #3 ... https://forum.hptuners.com/showthread.php?110791-Stock-2012-5-3-severe-knock-retard!

About the transmission being in a gear it's not supposed to. Are we talking hardware failure?