Homepage Garage Wiki Register Social Groups Calendar Search Today's Posts Mark Forums Read
#Camaro6
Go Back   CAMARO6 > Technical Camaro Topics > Road Course/Track and Autocross


AWE Tuning


Post Reply
 
Thread Tools
Old 10-06-2019, 03:27 PM   #1
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
'18 ZL1 A10 - full throttle surging on track

Yesterday we ran our ZL1 at Wild Horse Pass East course in Phoenix, and I was experiencing full throttle surging/hesitation on the straights.

'18 ZL1 A10, ~11k miles
Stock GY supercar 3 tires
Mix of pump 91 and 100 unleaded, calculated ~94 octane.

Ambient temps in the mid 90s

When I first felt it, I was running PTM Sport 1, and I thought it might be the traction control/ stability control, but it was only happening at full throttle on the straights, so I thought that was unlikely. I ran the car in Sport 2 and Race, and it did it in every mode.

The surging was present on straights after left and right turns, and the chicane (right/left). It was more apparent the harder the car was pushed... my wife didn't experience nearly to the extent I did, but she did tell me it was noticable even at her pace.

I've never experienced this on the street, though the car has been run to ~140 a couple of times on a 'private, closed course'.

The following video is a clip from one session where you can see/hear the surging/hesitation.

It's subtle, but there at 00:16 in 3rd, 00:20 in 4th. It's really obvious at 00:32 in 3rd gear. You can see in the video that the TC icon is not coming on when it occurs.



After researching here, I found the TSB for the wiring harness rubbing on the body, which has not been addressed as far as I know. A quick look shows no exposed wires, but it is clear the sheet metal is wearing into the plastic corrugated tubing around the harness.

I also found the thread on the belt rubbing the wiring harness. That does not appear to be the problem.

There is also a member here who is on his third fuel pump, with a similar issue, but he reports it also happens in the corners.

Anyone experience this issue with their ZL1/ZLE?? Any ideas?

I'll be taking it to the dealer tomorrow, but I'd like to be armed with as much info as possible.
Rodan is offline   Reply With Quote
Old 10-06-2019, 04:46 PM   #2
Badmojo
aka BeastZL1
 
Badmojo's Avatar
 
Drives: 2019 Camaro ZL1 1LE, 2004 Cobra
Join Date: Dec 2017
Location: NC
Posts: 1,087
I suggest not racing in Sport 1. It's hard to tell, but the engine is cutting power on purpose. Some guys have had air in the intercooler loop and the engine pulls power on high-IAT. You can also pull the battery cable, but I wouldn't do that until after you take it in. You don't want to clear any codes.



Please report back with what you find out.
__________________
2019 Camaro ZL1 1LE
Racing for ALS Youtube Link
Badmojo is offline   Reply With Quote
Old 10-06-2019, 05:16 PM   #3
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
I can understand it pulling power for high IATs... it was hot out.

But I wouldn't expect it to cut in/out causing surging.
Rodan is offline   Reply With Quote
Old 10-06-2019, 05:54 PM   #4
GunMetalGrey

 
GunMetalGrey's Avatar
 
Drives: Track prepped 2018 Camaro ZL1 (a10)
Join Date: Aug 2013
Location: Victoria B.C. Canada
Posts: 1,376
Good to know it's doing it after left and right corners for you, I've only have hard long right corners, so I don't know if mine would act up on left corners, but I assume it would.



I'd suggest trying to find a long hard corner, like a looping on or off ramp to a highway, to see if you can recreate the problem, that would give your dealership more info to work with.


Unfortunately my dealership just kept saying it was a defective fuel pick up assembly/pump, I'm taking my car back in this week to see if they will actually do some detective work instead of just throwing new parts at my car, I'll keep you posted.
__________________
2018 ZL1; Mag 2650, 2" LT Headers and intake, a bunch of SPL suspension upgrades, YYZ springs, sway bars, APEX wheel and SC3R's
GunMetalGrey is offline   Reply With Quote
Old 10-07-2019, 11:35 AM   #5
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
Dropped it off at the dealer this morning.

They're going to do the wiring harness TSB, and see if any codes show up.
Rodan is offline   Reply With Quote
Old 10-07-2019, 05:41 PM   #6
GunMetalGrey

 
GunMetalGrey's Avatar
 
Drives: Track prepped 2018 Camaro ZL1 (a10)
Join Date: Aug 2013
Location: Victoria B.C. Canada
Posts: 1,376
Quote:
Originally Posted by Rodan View Post
Dropped it off at the dealer this morning.

They're going to do the wiring harness TSB, and see if any codes show up.
Thanks for update, looking forward to hearing what they say
__________________
2018 ZL1; Mag 2650, 2" LT Headers and intake, a bunch of SPL suspension upgrades, YYZ springs, sway bars, APEX wheel and SC3R's
GunMetalGrey is offline   Reply With Quote
Old 10-08-2019, 08:58 AM   #7
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
Dealer is waiting for the part to complete the TSB, but no codes were set by the surging so they're clueless.

This is what I was afraid of... without codes or being able to duplicate the problem the dealer is essentially refusing to do anything.

I'm looking into getting the car on a dyno in Phoenix with a good GM performance shop to see if we can duplicate the problem. Other than that, I'm not sure what to do.

Anyone have a contact at GM customer service that isn't clueless about these cars?
Rodan is offline   Reply With Quote
Old 10-08-2019, 05:59 PM   #8
GunMetalGrey

 
GunMetalGrey's Avatar
 
Drives: Track prepped 2018 Camaro ZL1 (a10)
Join Date: Aug 2013
Location: Victoria B.C. Canada
Posts: 1,376
Quote:
Originally Posted by Rodan View Post
Dealer is waiting for the part to complete the TSB, but no codes were set by the surging so they're clueless.

This is what I was afraid of... without codes or being able to duplicate the problem the dealer is essentially refusing to do anything.

I'm looking into getting the car on a dyno in Phoenix with a good GM performance shop to see if we can duplicate the problem. Other than that, I'm not sure what to do.

Anyone have a contact at GM customer service that isn't clueless about these cars?
You don't have any long hard corners you can replicate this on?
I had to take this approach until my car started throwing codes, but it only started throwing codes because I got the car to act up a lot more by repeating what caused it over and over again, also the less fuel it had in the tank the more it started to throw codes.
When I was down to 1/8 tank it got so severe I thought I wrecked my car at one point, it basically went into some sort of limp mode and slowly died on the side of the road. That created a check engine light. The car finally restarted and I drove it straight to the dealership.
__________________
2018 ZL1; Mag 2650, 2" LT Headers and intake, a bunch of SPL suspension upgrades, YYZ springs, sway bars, APEX wheel and SC3R's
GunMetalGrey is offline   Reply With Quote
Old 10-08-2019, 07:13 PM   #9
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
Quote:
Originally Posted by GunMetalGrey View Post
You don't have any long hard corners you can replicate this on?
It doesn't occur in corners. Only at full throttle on a straight. Short of Talledega or Daytona, I can't think of a corner that you can put a ZL1 through at full throttle.

It also did it with a full tank... and never below 1/2 tank.

I don't think my problem is the same as yours, though the fuel pump is still a possibility. Given that you're on your third, I'm not sure the fuel pump is your problem, either....
Rodan is offline   Reply With Quote
Old 10-08-2019, 07:15 PM   #10
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
Picking the car up later tonight. Dealer didn't do anything other than the wiring harness TSB.

"If we can't replicate it, and it doesn't throw a code, how can we do anything?"

Service manager is on vacation. I'll be chatting with him next week.
Rodan is offline   Reply With Quote
Old 10-08-2019, 07:23 PM   #11
arpad_m


 
arpad_m's Avatar
 
Drives: 2018 Camaro 2SS A8
Join Date: Jul 2017
Location: East Tennessee
Posts: 11,490
A somewhat long shot, but if you can replicate the issue at will, how about logging it with HP Tuners (VCM Scanner) and asking your tuner to help diagnose it?
__________________
2018 Camaro 2SS — G7E MX0 NPP F55 IO6
735 rwhp | 665 rwtq

Magnuson TVS 2300 80mm pulley | Kooks 1 7/8" LT headers | JRE smooth idle terminator cam | LT4 FS & injectors | TSP forged pistons & rods
JMS PowerMAX | DSX flex fuel kit | Roto-Fab CAI | Soler 95mm LT5 TB | 1LE wheels | 1LE brakes | BMR rear cradle lockout | JRE custom tune

1100 - 1/30/18 | 2000 - 1/31/18
3000 - 2/06/18 TPW 2/26/18
3400 - 2/19/18 | 3800 - 2/26/18
4300 - 2/27/18 | 4B00 - 3/01/18
4200 - 3/05/18 | 4800 - 3/14/18
5000 - 3/16/18 | 6000 - 3/19/18
arpad_m is offline   Reply With Quote
Old 10-08-2019, 07:43 PM   #12
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
Quote:
Originally Posted by arpad_m View Post
A somewhat long shot, but if you can replicate the issue at will, how about logging it with HP Tuners (VCM Scanner) and asking your tuner to help diagnose it?
The issue only appeared a lap or more into hard track running. Trying to duplicate that on the street would not be a good idea.

I'm looking into a couple of shops in Phoenix where we might be able to duplicate it on the dyno. Of course, that's a 100 mile drive, and I'll have to pay out of pocket and hope GM will reimburse.
Rodan is offline   Reply With Quote
Old 10-08-2019, 09:43 PM   #13
Rodan
 
Rodan's Avatar
 
Drives: 2018 ZL1 coupe
Join Date: Nov 2018
Location: Prescott, Arizona
Posts: 589
I downloaded the Cosworth software to dig a little deeper into the PDR data. Throttle is showing 100% during the surging, so at least the computer is seeing full throttle input.

Temps all look pretty good considering the hot conditions.

What I found interesting was the inconsistency of boost pressure from lap to lap... FYI, lap 4 is the lap the clip in the OP was taken from.



Even with traffic and varying lap times, full throttle occurs in every lap, but boost pressure varies quite a bit. Has anyone looked at their data? Seeing something similar?
Rodan is offline   Reply With Quote
Old 10-12-2019, 09:55 PM   #14
GunMetalGrey

 
GunMetalGrey's Avatar
 
Drives: Track prepped 2018 Camaro ZL1 (a10)
Join Date: Aug 2013
Location: Victoria B.C. Canada
Posts: 1,376
I took a mechanic from my dealership for a test drive yesterday while he hooked up his computer to my car to measure my cars data, while I don’t have that data to display here, when I took him on a long hard corner he called out the drastic drop in fuel pressure about one second before my car started to bog, choke and lose power.

Since I am already on my 3rd fuel pickup assembly in less than one year, he is going to call GM and start doing some research and let me know what he finds, as soon as he has any info I’ll share it.

To the OP, if the challenge I’m having with my car is different than yours, I’ll stop posting on this thread, up until now it is unclear to me if we are experiencing the same problem, your thoughts?
__________________
2018 ZL1; Mag 2650, 2" LT Headers and intake, a bunch of SPL suspension upgrades, YYZ springs, sway bars, APEX wheel and SC3R's
GunMetalGrey is offline   Reply With Quote
 
Post Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 03:50 AM.


Powered by vBulletin® Version 3.8.9 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.