[cwebster]

I noticed recently that my engine was producing less power at low RPM than that to which I've become accustomed. Sometimes it would even misfire/hesitate on WOT from stop or low speed (5-10 MPH). At first I reasoned that it may just be the "nannies" (TC) kicking in to keep me from spinning the tires. So I turned TPM completely off by holding down the SC button for more than 5 secs. Although I didn't experience additional misfires, it did still appear to be underpowered. Previously, mashing the gas at 5-10 MPH in 1st gear would immediately spin the tires on pavement if drive mode was "Track" and TPM mode was "Race".

Has anyone else experienced this?

I remember when this used to happen on my 5th Gen SS 1LE it was an indication that the ECM had "slipped" into the low-octane tables. At that time the consensus was that some gasoline suppliers had less than 93 octane at their "93" pumps. Some members reported that their dealers were putting low octane fuel in before delivery. Also, some owners were putting 89-91 octane fuel in their tanks either out of ignorance or mandated by their state. If octane rating is low enough, this would trigger the ECM to change air-fuel ratio for a lower octane fuel. Someone came up with a "fuse pull" to reset the ECM to use the high-octane tables. Apparently, the ECM would not reset on its own even if the owner repeatedly filled the tank with 93 octane gas.

I wonder if the 6th Gen Camaros suffer from the same issue. I don't have any tuning tools so I can't read which tables my ECM is using. So, I decided to go ahead and pull all the ECM fuses to see if it makes a difference. I pulled the fuses indicated below yesterday morning and haven't driven it since. After I post this I'll put the fuses back and take it for a drive to see if there's a difference. Then I'll report back.

On the 5th Gen SS 1LE it was fuses 5 and 20.

Fuse 5: Engine Control Module Main
Fuse 20: Engine Control Module/Ignition

On the 6th Gen ZL1, the following are corresponding fuses. I only saw 3 related to ECM.

F57: 15A ECM IGN
F66: 25A ECM 1
F67: 10A ECM 2

[Update]

The fuse block containing these fuses is on the right side of the engine bay (on left if standing in front of car).

Note: I'm just guessing on this for the ZL1, based on my experience with the 5th Gen SS 1LE. This may or may not help but I don't see how it can hurt as long as the fuses get put back in the right place before starting again.




--Cal

[Sven59]

Originally Posted by cwebster

I noticed recently that my engine was producing less power at low RPM than that to which I've become accustomed. Sometimes it would even misfire/hesitate on WOT from stop or low speed (5-10 MPH). At first I reasoned that it may just be the "nannies" (TC) kicking in to keep me from spinning the tires. So I turned TPM completely off by holding down the SC button for more than 5 secs. Although I didn't experience additional misfires, it did still appear to be underpowered. Previously, mashing the gas at 5-10 MPH in 1st gear would immediately spin the tires on pavement if drive mode was "Track" and TPM mode was "Race".

Has anyone else experienced this?

I remember when this used to happen on my 5th Gen SS 1LE it was an indication that the ECM had "slipped" into the low-octane tables. At that time the consensus was that some gasoline suppliers had less than 93 octane at their "93" pumps. Some members reported that their dealers were putting low octane fuel in before delivery. Also, some owners were putting 89-91 octane fuel in their tanks either out of ignorance or mandated by their state. If octane rating is low enough, this would trigger the ECM to change air-fuel ratio for a lower octane fuel. Someone came up with a "fuse pull" to reset the ECM to use the high-octane tables. Apparently, the ECM would not reset on its own even if the owner repeatedly filled the tank with 93 octane gas.

I wonder if the 6th Gen Camaros suffer from the same issue. I don't have any tuning tools so I can't read which tables my ECM is using. So, I decided to go ahead and pull all the ECM fuses to see if it makes a difference. I pulled the fuses indicated below yesterday morning and haven't driven it since. After I post this I'll put the fuses back and take it for a drive to see if there's a difference. Then I'll report back.

On the 5th Gen SS 1LE it was fuses 5 and 20.

Fuse 5: Engine Control Module Main
Fuse 20: Engine Control Module/Ignition

On the 6th Gen ZL1, the following are corresponding fuses. I only saw 3 related to ECM.

F57: 15A ECM IGN
F66: 25A ECM 1
F67: 10A ECM 2

--Cal

A lot of debate in the 5th gen if it actually worked, many said it resets on its own.

[mlee]

Originally Posted by Sven59

A lot of debate in the 5th gen if it actually worked, many said it resets on its own.

Maybe in the later years but there is absolutely no doubt this was a fix for the early L99 cars.

However, I seriously doubt this is an issue in the 6th Gen. Track times have back up the power claims

[cwebster]

Originally Posted by mlee

Maybe in the later years but there is absolutely no doubt this was a fix for the early L99 cars.

However, I seriously doubt this is an issue in the 6th Gen. Track times have back up the power claims

Agreed. I can confirm it was an issue with my 2014 SS 1LE and that the fuse pull did, in fact, "revive" the power.

6th Gen power claims and validation aside, the octane table issue was always a transient one.

(all this done below with zero traffic and never exceeded speed limit)

Just got back from running errands and testing my fuse pull. She's alive again! After putting back the fuses, I started her up and let the engine idle until the RPM settled. Meanwhile, I changed drive mode to "Track" and TPM mode to "Race", like it was when I was experiencing the issue. With coolant temps still cold, I slowly left my neighborhood. Once on the state road I eased it up to 20 MPH and punched it. Tires spun easily. Once more to be sure... yup, plenty of power on the low end without hesitation.

I ran my errands and returned home. When on the state road again, I slowed to 20 MPH and punched it. This time, with the tires warmed up, not as much wheel spin but no hesitation whatsoever and plenty of low-end torque. Slowed and repeated twice to verify.

This was admittedly very un-scientific, especially since I'd also switched to the K&N air filter. Still, even if the improvement was all due to the air filter or some un-repeatable atmospheric conditions, I feel like I've got another tool in my back pocket. Even if it has no effect, it hurts nothing and makes me feel better.

I know there'll be some who feel I deserve to be flogged for suggesting this so let the roasting begin...

--Cal

[Sven59]

http://www.camaro5.com/forums/showthread.php?t=371551

Sent from my SM-G955U using Tapatalk

[Sven59]

Originally Posted by Sven59

http://www.camaro5.com/forums/showthread.php?t=371551

Sent from my SM-G955U using Tapatalk

See post #26

Sent from my SM-G955U using Tapatalk

[dcosta]

Originally Posted by cwebster

Agreed. I can confirm it was an issue with my 2014 SS 1LE and that the fuse pull did, in fact, "revive" the power.

6th Gen power claims and validation aside, the octane table issue was always a transient one.

(all this done below with zero traffic and never exceeded speed limit)

Just got back from running errands and testing my fuse pull. She's alive again! After putting back the fuses, I started her up and let the engine idle until the RPM settled. Meanwhile, I changed drive mode to "Track" and TPM mode to "Race", like it was when I was experiencing the issue. With coolant temps still cold, I slowly left my neighborhood. Once on the state road I eased it up to 20 MPH and punched it. Tires spun easily. Once more to be sure... yup, plenty of power on the low end without hesitation.

I ran my errands and returned home. When on the state road again, I slowed to 20 MPH and punched it. This time, with the tires warmed up, not as much wheel spin but no hesitation whatsoever and plenty of low-end torque. Slowed and repeated twice to verify.

This was admittedly very un-scientific, especially since I'd also switched to the K&N air filter. Still, even if the improvement was all due to the air filter or some un-repeatable atmospheric conditions, I feel like I've got another tool in my back pocket. Even if it has no effect, it hurts nothing and makes me feel better.

I know there'll be some who feel I deserve to be flogged for suggesting this so let the roasting begin...

--Cal

The real difference with lighting up the tires I
have noticed is the street surface..some surfaces are easier than others the burn these tires..

[cwebster]

Originally Posted by dcosta

The real difference with lighting up the tires I
have noticed is the street surface..some surfaces are easier than others the burn these tires..

Same street as I originally verified the issue. Slightly different atmospheric conditions but I don't see that as a major contributor. I've lit up the tires many times since I picked up my car in Dec. under a wide variety of conditions. Went through my first set of rear tires in 2 months. By now I know my car... this was out of the ordinary.

--Cal

[cwebster]

Originally Posted by Sven59

See post #26

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Thanks for digging up the reference.

So if the ECM "recovers" on its own and pulling the fuses forces the recovery sooner, as "ZO6 Bryan" said, then it's not a "myth". The fuse pull did work. I once waited a few days to see if it would reset on its own but I lost patience. After that, as soon as I felt low-end power loss I pulled 'em.

Anyway, as I said above, it can't hurt anything as long as I put them back before starting the motor. Worst case, I've wasted a few minutes of time.

Cheers!

--Cal

[Sven59]

Exactly, some people say they feel a difference some don't. I think some people feel a difference because they pull it at night and maybecolder in the AM. These cars definitely like cooler temps.

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[cwebster]

Originally Posted by Sven59

Exactly, some people say they feel a difference some don't. I think some people feel a difference because they pull it at night and maybecolder in the AM. These cars definitely like cooler temps.

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Yup. My car has the same temperament as me. We both like cooler temps. That's why I waited 'til mid-afternoon to take the drive. It was around 80-ish with about 50% humidity. It was cooler and probably same humidity the night I experienced the hesitation and misfire a few days ago, so I felt like it was a good test.

Anyway, I definitely feel better now. Got a breath of fresh air with my K&N filter, no more low-power issues, clean motor oil, gear-box lube, and transmission fluid... I'm ready to roll this weekend if thunderstorms clear up in time for Test & Tune Friday.

--Cal

[bobby35ny]

To the OP,
Anything noticeable with the K&N drop in filter?
-bobby

[cwebster]

Originally Posted by bobby35ny

To the OP,
Anything noticeable with the K&N drop in filter?
-bobby

I didn't change it to resolve any issues. I did it more to ensure that I had good, unrestricted air flow to stack the deck in my favor at the track. When I heard about the service bulletin citing bad filters in the thread "UPDATE! 5000 RPM Limit" Post #50, I felt like changing it would also side-step any potential failures I might see in the future. K&N has a good reputation for their low-restriction aftermarket filters. I honestly can't attribute any gains to it yet, though. Unless I did a dyno pull before and after installing it, I doubt if I could positively attribute any gains to the filter anyway. I'll be happy if I get to the track this weekend and improve on my 60' times and ET/MPH. If improvements are not due to the new filter, it must be my technique and/or skills. Either way I'll be happy.

--Cal

[mlee]

Originally Posted by Sven59

See post #26

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I pretty much agree with this post except for the early L99 Auto Cars did in fact have the issue as verified by GM engineers.
After that happened everyone jumped on the bandwagon. It quickly became it doesn't hurt to try it and some claimed improvements.

Originally Posted by Sven59

Exactly, some people say they feel a difference some don't. I think some people feel a difference be cause they pull it at night and maybe colder in the AM. These cars definitely like cooler temps.

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Butt dyno and feel proves nothing for me. But that's just me..