LFX getting lots of KR - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

TehWingman · 03-20-2016, 12:54 AM

When I start to dip into the throttle the car falls on its face. Happens mostly at half to 75% throttle below 5k rpm. Only mods are Rotofab intake and Vmax TB. Tune is completely stock. Not sure what is causing all this KR. It seems to be worse when the ambient air temp is cooler. Any ideas on what the hell is going on? It's been going on for a while and I'm getting the general consensus that the intake is causing issues.

Log file is posted on HPT forums here http://www.hptuners.com/forum/showth...383#post423383

IneedAZ · 03-20-2016, 06:51 AM

What octane? Tried a different gas station? I have had it do similar with bad gas

ghosted · 03-20-2016, 07:03 AM

Even when I use 91 octane (no 93 in AZ), I get tons of KR. I stepped it up, and when mixing 91/100 octane to equal around 94 octane, I get zero KR.

TehWingman · 03-20-2016, 01:43 PM

A while ago I went from mid grade to 93. Didn't help. Always go to one of 2 Shell stations around town. I'm seeing a lot of misfires as well - and the "Fuel System #1 Status (SAE)" PID is reporting "OL - Fault", which I'm not familair with.

I have been battling issues with the car from almost day 1. took 2 different dealerships 4 times to correctly diagnose and repair a corroded main harness connection block at the firewall because water was leaking into it. It intermittently had random codes and intermittently ran rough. (Still smells musty around and in the HVAC blower). I was a f/i Cobalt tuning guru so I'm not a tuning newbie, just never worked with an LFX before, or anything newer than 2010 model year. Things have changed a LOT in these PCMs.

Going to throw the stock intake back on, reset trims, and see if things get any better.

TehWingman · 03-20-2016, 08:34 PM

Stock intake back on and reset fuel trims. Even more KR now, and I get it lower in the rpm range too.

JMT · 03-20-2016, 09:49 PM

Check your maf it might be the sensor has dirt/oil on it

hawk02 · 03-20-2016, 10:05 PM

Your only variable now is the VMax ported TB. I supposed you sent back your stock TB for the core refund? I logged slightly more knock retard on my ZL1, especially during rapid changes in throttle position, when I had a VMax on it. I went back to the the stock TB and while it didn't completely eliminate all the retard, it reduced it by a noticeable amount.

Elite Engineering · 03-22-2016, 02:33 AM

Knock retard is generally from detonation. Causes are poor fuel quality, too low of octane, over heating, and one of the most common is oil ingestion. What are you doing to stop the ingestion? The LLT is 11.3:1 CR and the LFX 11.5:1 CR so it is critical for optimum performance and efficiency to run premium fuel (yes, the owners manual states 87...but the KR is far higher so you are not running optimum timing advance, etc.) and to stop that oil ingestion. Most "catchcans" will do little as they allow more oil to pass through than they trap (all cans trap some) and the problem will still exist. Take your TB off and reach into the IM snout and dip your finger into the cast in depression just inside the opening. It should be full of oil. This is most likely the main cause if your running a 93 octane fuel. The E2 and E2-X Catch Can system is made just for GDI engines that cannot tolerate any oil (unlike a port injection engine that can tolerate some) and is the most effective separation system available currently.

willoverkill · 03-22-2016, 02:14 PM

Can't look at the scan right now but its not uncommon for new GM factory tunes to rely on what's called spark knock learn. There's two tables you'll see in your tune, and the computer has the ability to interpolate between the two tables at any given point if there's consistent spark knock at that point above a certain degree.

If you keep resetting the tune with a flash or etc, this resets the spark adaptives as well.

This is partly why in an Overkill tune I've spent so much tune reconstructing the spark tables to rely less on spark adaptives. As part of your tuning, you should be discovering where the spark knock is occuring and revise the high octane main spark table at those points

TehWingman · 03-27-2016, 09:31 PM

Well, Elite hit the nail on the head. Pulled the intake mani off and it was covered in oil with the intake and exhaust valves coked with carbon/oil deposits.

I run 91 / 93 octane. Just made the car feel better when I switched from dealer supplied 87 to the premium.

I do run the elite catch can on the passenger side PCV, but nothing on the driver side PCV. That tube coming into the intake is wet with oil, the tube coming from the elite catch can is dry.

Since it's still warrantied i took it to the dealer and they did the top end cleaning and it feels like a new car again.

Anyone run another catch can on the driver side?

I freaking hate GM's Direct Injection.

Tajefe Couple · 03-28-2016, 01:05 AM

Quote:

Originally Posted by TehWingman

Well, Elite hit the nail on the head. Pulled the intake mani off and it was covered in oil with the intake and exhaust valves coked with carbon/oil deposits.

I run 91 / 93 octane. Just made the car feel better when I switched from dealer supplied 87 to the premium.

I do run the elite catch can on the passenger side PCV, but nothing on the driver side PCV. That tube coming into the intake is wet with oil, the tube coming from the elite catch can is dry.

Since it's still warrantied i took it to the dealer and they did the top end cleaning and it feels like a new car again.

Anyone run another catch can on the driver side?

I freaking hate GM's Direct Injection.

I use a clean side separator from Elite with the catch can to eliminate this issue. Link and picture below. Please ignore the red as I was answering a question.
http://www.eliteengineeringusa.com/c...oil-separator/
Intake manifold is always dry now.

TehWingman · 03-28-2016, 02:44 PM

I think that is what I need, but can it be used below 32 degrees? I drive the car in the winter and wanted to get the separator that the 1LE uses but that can't be used below freezing according to GM.

Tajefe Couple · 03-28-2016, 10:58 PM

Quote:

Originally Posted by TehWingman

I think that is what I need, but can it be used below 32 degrees? I drive the car in the winter and wanted to get the separator that the 1LE uses but that can't be used below freezing according to GM.

I don't think they recommend it, would just see if Elite answers you or ask them directly.

TehWingman · 04-03-2016, 11:12 PM

I took the catch can apart today and while it is catching a lot of oil, much is still getting through to the intake manifold. The coalescing media was soaked in oil, the hose to the IM had oil residue in it, and the front of the IM under the hose fitting was coated with oil. The "Clean side" pcv was dry.

I wish I knew why i was sucking in so much more oil than most. Every few hundred miles I get a couple ounces of oil in the can, and that's just what is being caught.

03-20-2016, 06:51 AM	#2
IneedAZ Drives: 2017 ZL1 A10 & 2021 BMW M340i x Dr Join Date: Mar 2009 Location: Tampa Posts: 5,111 View My Garage	What octane? Tried a different gas station? I have had it do similar with bad gas __________________ Sold 2012 2LT RS 12.3@112 old setup Sold 1967 Camaro Pro Street. Ran 10's mild BB on NOS. 2017 HyperBlue ZL1 A10 Born 3/17/17Delivered 4/08/17 2020 Build: Mag2650, BTR Stage2, NW103, BG, 14% lower, 90mm upper, ARH 2" Long system w/no cats, SW Legend mufflers. 807hp/762tq on 93 gas and 848hp/792tq on e47 Sold 2018 (Go Mango) Dodge Charger Daytona 392 Daily Driver Daily Driver 2021 BMW M340i Xdrive

03-20-2016, 07:03 AM	#3
ghosted BCS Auto Drives: 2015 Camaro 1LS Join Date: Dec 2015 Location: Phoenix, AZ Posts: 1,299 View My Garage	Even when I use 91 octane (no 93 in AZ), I get tons of KR. I stepped it up, and when mixing 91/100 octane to equal around 94 octane, I get zero KR. __________________ BCS Auto on Facebook - - - Follow me on Instagram @datv6tho & @officialbcsauto

03-20-2016, 10:05 PM	#7
hawk02 Coupe Newbie Drives: '23 CT5-V BW, '21 Corvette HTC Join Date: Jul 2011 Location: Columbus, Ohio Posts: 3,439 View My Garage	Your only variable now is the VMax ported TB. I supposed you sent back your stock TB for the core refund? I logged slightly more knock retard on my ZL1, especially during rapid changes in throttle position, when I had a VMax on it. I went back to the the stock TB and while it didn't completely eliminate all the retard, it reduced it by a noticeable amount. __________________

03-27-2016, 09:31 PM	#10
TehWingman Camaros love stripes. Drives: 2014 Camaro 1LS Join Date: Aug 2014 Location: Hubbard, Ohio Posts: 69 View My Garage	Well, Elite hit the nail on the head. Pulled the intake mani off and it was covered in oil with the intake and exhaust valves coked with carbon/oil deposits. I run 91 / 93 octane. Just made the car feel better when I switched from dealer supplied 87 to the premium. I do run the elite catch can on the passenger side PCV, but nothing on the driver side PCV. That tube coming into the intake is wet with oil, the tube coming from the elite catch can is dry. Since it's still warrantied i took it to the dealer and they did the top end cleaning and it feels like a new car again. Anyone run another catch can on the driver side? I freaking hate GM's Direct Injection. Last edited by TehWingman; 03-27-2016 at 09:44 PM.

03-20-2016, 12:54 AM	#1
TehWingman Camaros love stripes. Drives: 2014 Camaro 1LS Join Date: Aug 2014 Location: Hubbard, Ohio Posts: 69 View My Garage	LFX getting lots of KR When I start to dip into the throttle the car falls on its face. Happens mostly at half to 75% throttle below 5k rpm. Only mods are Rotofab intake and Vmax TB. Tune is completely stock. Not sure what is causing all this KR. It seems to be worse when the ambient air temp is cooler. Any ideas on what the hell is going on? It's been going on for a while and I'm getting the general consensus that the intake is causing issues. Log file is posted on HPT forums here http://www.hptuners.com/forum/showth...383#post423383

03-20-2016, 01:43 PM	#4
TehWingman Camaros love stripes. Drives: 2014 Camaro 1LS Join Date: Aug 2014 Location: Hubbard, Ohio Posts: 69 View My Garage	A while ago I went from mid grade to 93. Didn't help. Always go to one of 2 Shell stations around town. I'm seeing a lot of misfires as well - and the "Fuel System #1 Status (SAE)" PID is reporting "OL - Fault", which I'm not familair with. I have been battling issues with the car from almost day 1. took 2 different dealerships 4 times to correctly diagnose and repair a corroded main harness connection block at the firewall because water was leaking into it. It intermittently had random codes and intermittently ran rough. (Still smells musty around and in the HVAC blower). I was a f/i Cobalt tuning guru so I'm not a tuning newbie, just never worked with an LFX before, or anything newer than 2010 model year. Things have changed a LOT in these PCMs. Going to throw the stock intake back on, reset trims, and see if things get any better.

03-20-2016, 08:34 PM	#5
TehWingman Camaros love stripes. Drives: 2014 Camaro 1LS Join Date: Aug 2014 Location: Hubbard, Ohio Posts: 69 View My Garage	Stock intake back on and reset fuel trims. Even more KR now, and I get it lower in the rpm range too.

03-20-2016, 09:49 PM	#6
JMT Drives: 2013 1LT Join Date: Oct 2013 Location: Panama City Beach, FL Posts: 703 View My Garage	Check your maf it might be the sensor has dirt/oil on it

03-22-2016, 02:33 AM	#8
Elite Engineering Drives: 2010 Camaro Join Date: Nov 2009 Location: Denver Posts: 1,383	Knock retard is generally from detonation. Causes are poor fuel quality, too low of octane, over heating, and one of the most common is oil ingestion. What are you doing to stop the ingestion? The LLT is 11.3:1 CR and the LFX 11.5:1 CR so it is critical for optimum performance and efficiency to run premium fuel (yes, the owners manual states 87...but the KR is far higher so you are not running optimum timing advance, etc.) and to stop that oil ingestion. Most "catchcans" will do little as they allow more oil to pass through than they trap (all cans trap some) and the problem will still exist. Take your TB off and reach into the IM snout and dip your finger into the cast in depression just inside the opening. It should be full of oil. This is most likely the main cause if your running a 93 octane fuel. The E2 and E2-X Catch Can system is made just for GDI engines that cannot tolerate any oil (unlike a port injection engine that can tolerate some) and is the most effective separation system available currently.

03-22-2016, 02:14 PM	#9
willoverkill Drives: Fast Join Date: Dec 2012 Location: Nanaimo BC Posts: 220	Can't look at the scan right now but its not uncommon for new GM factory tunes to rely on what's called spark knock learn. There's two tables you'll see in your tune, and the computer has the ability to interpolate between the two tables at any given point if there's consistent spark knock at that point above a certain degree. If you keep resetting the tune with a flash or etc, this resets the spark adaptives as well. This is partly why in an Overkill tune I've spent so much tune reconstructing the spark tables to rely less on spark adaptives. As part of your tuning, you should be discovering where the spark knock is occuring and revise the high octane main spark table at those points

03-28-2016, 02:44 PM	#12
TehWingman Camaros love stripes. Drives: 2014 Camaro 1LS Join Date: Aug 2014 Location: Hubbard, Ohio Posts: 69 View My Garage	I think that is what I need, but can it be used below 32 degrees? I drive the car in the winter and wanted to get the separator that the 1LE uses but that can't be used below freezing according to GM.

04-03-2016, 11:12 PM	#14
TehWingman Camaros love stripes. Drives: 2014 Camaro 1LS Join Date: Aug 2014 Location: Hubbard, Ohio Posts: 69 View My Garage	I took the catch can apart today and while it is catching a lot of oil, much is still getting through to the intake manifold. The coalescing media was soaked in oil, the hose to the IM had oil residue in it, and the front of the IM under the hose fitting was coated with oil. The "Clean side" pcv was dry. I wish I knew why i was sucking in so much more oil than most. Every few hundred miles I get a couple ounces of oil in the can, and that's just what is being caught.