2015 ZL1 knock? Conclusion @ 4/27/15 - Page 4 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Blueclyde · 04-02-2015, 07:53 PM

I'm wondering if your issue is the 91 octane fuel. Add an octane booster like Torco to see if it goes away. That would be the next step. It could be lower octane coming out of the pump than you think. These ECM's have knock learning software so the ECM should adjust to the fuel you regularly use. Not sure the dealer is going to be able to help with this. Try an octane booster before you take it back.

Lee Blue · 04-02-2015, 07:54 PM

Improperly gapped spark plug?

ZO6 Bryan · 04-02-2015, 08:42 PM

Quote:

Originally Posted by Chrispy

The fuse pull isn't over rated as it GUARANTEES you'll be in the high octane table.

Good luck!
Chris

It does no such thing. Maybe for 5 minutes. As soon as it picks up a knock signal you are right back in the low octane table.
And actually it is a blending of the high octane and low octane table determined by the KLF. The OP's "knock learn" function is obviously not working if he is still getting knock retard after several tanks of the same fuel.

ZO6 Bryan · 04-02-2015, 08:51 PM

Log the total spark advance on your dashlogic. You should be 22-23 degrees advance at WOT. But I am guessing it has "learned" down to 17-18 degrees. Then put some torco additive in. Or find some good 93 octane. Then log again. Both KR and total spark advance. If it improves greatly it may just be crap gas in your area.

Chrispy · 04-02-2015, 09:14 PM

Quote:

Originally Posted by ZO6 Bryan

It does no such thing. Maybe for 5 minutes. As soon as it picks up a knock signal you are right back in the low octane table.
And actually it is a blending of the high octane and low octane table determined by the KLF. The OP's "knock learn" function is obviously not working if he is still getting knock retard after several tanks of the same fuel.

We are saying exactly the same thing! It does exactly that. It resets to the high octane table after a fuse pull.

Again fill up at a new gas station, use a can of Torco, do the fuse pull and LOG.

You'll know your starting from the high octane table, you know you have more than enough octane for the stock tune and advance and you'll know if you no longer have KR or ticking that you have helped isolate one of the potential causes of the problem. (Bad gas)

ZO6 Bryan · 04-02-2015, 10:42 PM

Yes, pull the fuse to reset everything. But only after you fill it with some known good fuel with torco in it. Then it should begin to relearn from scratch. Then you shouldn't get any more knock retard. What concerns me is that the PCM has "learned" towards the low octane table but it still knocks. That's why I'd like to see what his total spark advance is at WOT. If it's learned down to 17 deg and still knocks? Anyone familiar with the gas they sell in his area? San Francisco?

KaBoom1701 · 04-02-2015, 11:12 PM

Quote:

Originally Posted by angryBits

I didn't get the #. I can ask about it next time I go in, but that won't be for a few weeks :/

I can wait. Thx

KaBoom1701 · 04-02-2015, 11:16 PM

Quote:

Originally Posted by angryBits

I don't have 93 here.

Though I'm very interested to hear more about the fuse pull to reset the car to the high octane table. What is that?

I'm going to guess the low octane table is to deal with the bad gas scenario? but if my car is using the low octane table, wouldn't it be less likely to knock? I'm totally guessing. Where can I get more info and procedure on the process?

Thanks!!

Buy a can of Torco and read this for the fuse pull info:

http://www.camaro5.com/forums/showthread.php?t=38964

Read post #3

http://www.camaro5.com/forums/showthread.php?t=249520

Six.Two SC · 04-02-2015, 11:54 PM

I have a '14 ZL1 with just a CAI Inc. I have to use shitty 91 too. I use the torque pro app and have seen knock retard up to 6 degrees. I added a 32 ounce can of Torco and pulled fuses 5 & 20 overnight. I've driven about 50 miles since and have not seen above 1.4 degrees of knock retard. No KR at WOT. Torco definitely made a difference. Add a can of Torco to a full tank and pull the fuses overnight before you take it to the dealer. These cars run terrible on 91 octane.

Sent from my iPhone using Tapatalk

LSX Camaro · 04-03-2015, 12:09 AM

Quote:

Originally Posted by angryBits

I got anxious and decided to take it in today. Exactly what I said would happen, happened...

He said, "That's normal".

In fact, he even said, "These cars knock all the time".

*sigh*

The tech went on a ride along with me and of course the car was much better behaved (I hate it when that happens). However, I was able to reproduce the issue a little and he didn't seem concerned. Though I'm not sure I trust this guy's opinion since he said "these cars knock all the time".

My problem with this is:
1. I drove 2 other ZL1s and neither of them made these noises.
2. I plan to add power mods in the future and want a healthy engine, not something that I don't trust and will live in fear of voiding my warranty.

You should go back to imports. Do us all a favor .

Six.Two SC · 04-03-2015, 12:20 AM

Should I be getting zero knock retard at anytime with approximately 95 octane with just a CAI?

Sent from my iPhone using Tapatalk

94tagt · 04-03-2015, 12:25 AM

Video looked/sounded pretty damn smooth as butter.

JeffInDFW · 04-03-2015, 12:45 AM

Quote:

Originally Posted by LSX Camaro

You should go back to imports. Do us all a favor .

He came from a 2013 GT500. Not sure why the asshat response. You can clearly see in the video he posted that he is indeed getting knock retard that should not be there. If the GM tech had been worth a crap, he would have checked for undue knock retard but didn't. Oh, I see you are a GM tech. A little touchy? Maybe jump in and offer the guy some advice instead of being a douche.

angryBits · 04-03-2015, 12:15 PM

Lots of posts, so I'll try to summarize:

- I've already been through several tanks of gas from several Top Tier gas stations. Always 91 Oct. The issue never faltered.

- I can try torco just to rule out gas, but I don't want to rely on torco -- I want to be able to run on pump gas.

- I have talked to people with ZL1's that live in the same area, running on the same 91 pump gas with no issues.

- I have driven 3 ZL1's and mine is the only one knocking.

Based on this, I'm fairly certain my car is not normal and fairly certain its not a fuel issue.

At the moment, I'm thinking bad MAF Sensor, bad injectors, bad fuel pump... maybe something obstructing the air intake? ... Running out of ideas. I'm hoping an Oil Separator will improve the issue if its a case of oil getting into the combustion chamber, but I shouldn't need it as others are not knocking and they don't have it.

I wasn't able to find the Air/Fuel Ratio on my DashLogic. Does anyone know how to set that up? This would tell me a lot more.

Thanks

04-02-2015, 08:51 PM	#46
ZO6 Bryan Drives: 02 Z06, 95 Trans Am, 2012 ZL1 Join Date: Mar 2012 Location: Southeast Posts: 1,838 View My Garage	Log the total spark advance on your dashlogic. You should be 22-23 degrees advance at WOT. But I am guessing it has "learned" down to 17-18 degrees. Then put some torco additive in. Or find some good 93 octane. Then log again. Both KR and total spark advance. If it improves greatly it may just be crap gas in your area. __________________ Bryan 2018 ZL1 M6

04-02-2015, 10:42 PM	#48
ZO6 Bryan Drives: 02 Z06, 95 Trans Am, 2012 ZL1 Join Date: Mar 2012 Location: Southeast Posts: 1,838 View My Garage	Yes, pull the fuse to reset everything. But only after you fill it with some known good fuel with torco in it. Then it should begin to relearn from scratch. Then you shouldn't get any more knock retard. What concerns me is that the PCM has "learned" towards the low octane table but it still knocks. That's why I'd like to see what his total spark advance is at WOT. If it's learned down to 17 deg and still knocks? Anyone familiar with the gas they sell in his area? San Francisco? __________________ Bryan 2018 ZL1 M6

04-02-2015, 11:54 PM	#51
Six.Two SC Drives: 2018 Summit White Camaro 1SS Join Date: Mar 2014 Location: Pasadena, CA Posts: 352	2015 ZL1 knock? Update @ 4/2/15 I have a '14 ZL1 with just a CAI Inc. I have to use shitty 91 too. I use the torque pro app and have seen knock retard up to 6 degrees. I added a 32 ounce can of Torco and pulled fuses 5 & 20 overnight. I've driven about 50 miles since and have not seen above 1.4 degrees of knock retard. No KR at WOT. Torco definitely made a difference. Add a can of Torco to a full tank and pull the fuses overnight before you take it to the dealer. These cars run terrible on 91 octane. Sent from my iPhone using Tapatalk __________________ '18 Satin White Vinyl Wrapped 1SS, 6MT, Low Gloss Black Wheels, NPP Dual Mode Exhaust Added: Diode Dynamics Black LED Sidemarkers, GM Dark Finish Tailights, GM ZL1 Black 3rd Brake Light, Black Plastidipped Bowties(front/rear), AFE Dry Drop In Filter, 12mm Spacers(front/rear)

04-03-2015, 12:20 AM	#53
Six.Two SC Drives: 2018 Summit White Camaro 1SS Join Date: Mar 2014 Location: Pasadena, CA Posts: 352	Should I be getting zero knock retard at anytime with approximately 95 octane with just a CAI? Sent from my iPhone using Tapatalk __________________ '18 Satin White Vinyl Wrapped 1SS, 6MT, Low Gloss Black Wheels, NPP Dual Mode Exhaust Added: Diode Dynamics Black LED Sidemarkers, GM Dark Finish Tailights, GM ZL1 Black 3rd Brake Light, Black Plastidipped Bowties(front/rear), AFE Dry Drop In Filter, 12mm Spacers(front/rear)

04-03-2015, 12:15 PM	#56
angryBits Drives: ZL1 1LE A10 Join Date: Mar 2015 Location: CA Posts: 1,093	Lots of posts, so I'll try to summarize: - I've already been through several tanks of gas from several Top Tier gas stations. Always 91 Oct. The issue never faltered. - I can try torco just to rule out gas, but I don't want to rely on torco -- I want to be able to run on pump gas. - I have talked to people with ZL1's that live in the same area, running on the same 91 pump gas with no issues. - I have driven 3 ZL1's and mine is the only one knocking. Based on this, I'm fairly certain my car is not normal and fairly certain its not a fuel issue. At the moment, I'm thinking bad MAF Sensor, bad injectors, bad fuel pump... maybe something obstructing the air intake? ... Running out of ideas. I'm hoping an Oil Separator will improve the issue if its a case of oil getting into the combustion chamber, but I shouldn't need it as others are not knocking and they don't have it. I wasn't able to find the Air/Fuel Ratio on my DashLogic. Does anyone know how to set that up? This would tell me a lot more. Thanks __________________ Current: 2019 ZL1 1LE A10 Mods: MPS4s Tires \| Borla Atak \| CF Steering Wheel Previous: 2018 ZL1 1LE M6 \| 2017 Z06 Z07 M7 \| 2017 GS A8 \| 2015 ZL1 M6 \| 2013 GT500

04-02-2015, 07:53 PM	#43
Blueclyde Drives: 2023 ZLE Join Date: Jun 2009 Location: Detroit Posts: 1,717	I'm wondering if your issue is the 91 octane fuel. Add an octane booster like Torco to see if it goes away. That would be the next step. It could be lower octane coming out of the pump than you think. These ECM's have knock learning software so the ECM should adjust to the fuel you regularly use. Not sure the dealer is going to be able to help with this. Try an octane booster before you take it back.

04-02-2015, 07:54 PM	#44
Lee Blue Drives: Zl1 summit white Join Date: Apr 2014 Location: Canada Posts: 7	Improperly gapped spark plug?

04-03-2015, 12:25 AM	#54
94tagt Drives: Pontiac Trans Am Join Date: Jun 2014 Location: lanterne rouge Posts: 97	Video looked/sounded pretty damn smooth as butter.