2014 Silverado TCC lockup

[Obsolete489]

Maybe commanding a leanish PE at those low rpm high load areas would be worth trying? Somewhere between stoich and the normal people eq ratio that I command?

Or just go straight to ~ .85 eq?

[IARLLC]

Sorry for the delay. Been in the air 14 of the last 17 hours. Now even less bright than usual I should also note that I don't know much about E85.

Yeah, GEN4 and GEN5 rely on the knock sensors pretty heavily. Pretty nearly everybody that reduces timing enough to get rid of KR reports worse fuel mileage and lower power. Might be interesting to log every type of retard and see where the source is coming from in each case. Some of what you are seeing after a shift might be Torque Management. While I don't get rid of it I do gradually add to the SPARK>ADVANCE>Minimum Spark tables from about .32 cyl airmass. Some raise them all of the way to 10 degrees but it really depends on the rig.

When carbon issues started coming up on GM DI motors GM started carefully suggesting a "decarbon" type cleaner be run through the intake pretty often. Then they said uh, maybe not....as some were cooking their cats during the process. If done often enough the valves and pistons won't get too much build-up so the cheap drip style method through the intake can be used carefully. I have heard of lots of guys having dealers pull their intake and wallnut blast the valves. Most of these rigs that I work on are run hard all of the time and still don't have a build-up at over 75k. There is another fleet that will not get run so hard but they are not getting driven enough to have any kind of result. It will probably be interesting to run a can of Seafoam or similar through it and see what you get (usually smokes really bad for a while if there was much build-up).

[Obsolete489]

Haha no worries man. I'm out deer hunting this weekend so my mind has been on that anyway.

That makes sense about the knock sensors. The factory tune threw KR all over which scared the hell out of me coming from tuning my old gen 3 computer truck. I think I'm going to start adding some timing back in and see what happens, obviously I won't let it go crazy with KR but a little more here and there is probably okay.

During shifts I can watch tm advance pull quite a bit of timing during shifts, but occasionally it will report KR too right after the shift completes.

And yeah I may try some seafoam in the tank and see if anything changes.

[IARLLC]

Cool. I am sooo jealous!

Seafoam through the tank should clean the injectors and help clean up the piston is it has some build-up. I guess people can put it in their oil too and it might help free up gummed up lifters or rings. But the way I use it on the GM DI rigs is through a small tube running it just ahead of the throttle body to clean up the intake a little and most importantly for the DI rig....the back of the valves. Without the injector spraying fuel on the back of the valve they get carbon/oil caked on....much worse with DOD/AFM as the super low vacuum level experienced during DOD highway cruise speed (heavy truck/4 cylinders). Anyway, the back of the valve issue causes rough starts and cold misfires, while carbon on the piston of course will increase occurrence of KR. So maybe running it through the tank will be the best way to see.

[Obsolete489]

I'm probably just going to spray down the intake and run some through the tank as well. I get a little sketched out when considering putting it directly in the oil haha.

Thanks for the help!

[kevin87turbot]

I'd be curious to see if you have the same results as I've been seeing just by changing oil.
Check this out...
https://www.youtube.com/watch?v=tPyM...ature=youtu.be
I've had good success with the Driven DI20. It has helped reduce knock in my DI vehicles.
Kevin

[Obsolete489]

Well, I do change my oil regularly. I couldn't find the second video pertaining to kr?