SS doesn't accelerate more than 135 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

RoadRunner70 · 03-01-2024, 02:07 AM

2011 Camaro SS auto/t, stock. Installed hubcentric wheel spacers. Mileage 121.000, gasoline 87,

This is not the first time I have noticed this. When approaching about 135 mph, noticeable vibrations and shaking begins. Looks like the car doesn't want to go faster than 135 mph, acceleration becomes very sluggish. Tranny in S mode and stabilitrak in competitive mode.

Previously I drove up to 155 mph without problems.

Maybe this is related, not sure. The fuel pump was replaced several months ago with the original one GM MU1959.
When fuel level is low (about 40 miles) the car starts to drive poorly and the traction disappears. Or sometimes it throws CEL related to the fuel pressure sensor or fuel control module. After refueling defect dissapears.
Idle fuel pressure is 3,9 bar per OBD readings.

Any suggestions?))

bsn · 03-01-2024, 04:28 AM

The first thing I would do is run 93 if you can get it, if not 91. 87 is an absolute no-no when your doing any type of performance driving. Second thing is NEVER do any performance driving with an empty tank, your sucking air and running lean and overheating your fuel pump, leading to burnt pistons and failed fuel pumps.

morepowerjoe · 03-01-2024, 06:27 AM

Quote:

Originally Posted by bsn

The first thing I would do is run 93 if you can get it, if not 91. 87 is an absolute no-no when your doing any type of performance driving. Second thing is NEVER do any performance driving with an empty tank, your sucking air and running lean and overheating your fuel pump, leading to burnt pistons and failed fuel pumps.

+1

gtstorey · 03-01-2024, 07:50 AM

What is fuel pressure when having the problem. Fuel pressure at idle doesn't mean much when the problem is WOT.

1JEWLDSSRS · 03-01-2024, 08:39 AM

Quote:

Originally Posted by bsn

The first thing I would do is run 93 if you can get it, if not 91. 87 is an absolute no-no when your doing any type of performance driving. Second thing is NEVER do any performance driving with an empty tank, your sucking air and running lean and overheating your fuel pump, leading to burnt pistons and failed fuel pumps.

+2 on this. 87 fuel isn't supposed to be used in an SS unless it is an emergency and you need fuel and can't get premium. Sos you shouldn't run the car hard at all with 87, knocking and detonation could accur and possible engine damage. Run a couple tanks of 91-93 through it and due the fuse pull reset.

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

Moto-Mojo · 03-01-2024, 09:18 AM

Must be running that Pemex fuel while doing top speed runs in, "Mexico", huh?

ZED SLED · 03-01-2024, 09:55 AM

Furthermore, once you've ran 87 in the early 5th gen SS, due to a software glitch you are stuck on the low octane fuel table and the only way to get back on the upper is to do the 5 & 20 fuse pull. IDK, they may have never fixed that for any model year 5th gen. Even made a sticky for this issue

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

Wizard1183 · 03-01-2024, 10:03 AM

Quote:

Originally Posted by Moto-Mojo

Must be running that Pemex fuel while doing top speed runs in, "Mexico", huh?

Pemex bought Shell Deer Park in Houston sir. So there’s a USA Pemex refinery….

d2cheer · 03-01-2024, 10:35 AM

Quote:

Originally Posted by ZED SLED

Furthermore, once you've ran 87 in the early 5th gen SS, due to a software glitch you are stuck on the low octane fuel table and the only way to get back on the upper is to do the 5 & 20 fuse pull. IDK, they may have never fixed that for any model year 5th gen. Even made a sticky for this issue

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

Is the 2013 affected by this?

Thanks,

Wizard1183 · 03-01-2024, 10:45 AM

Quote:

Originally Posted by d2cheer

Is the 2013 affected by this?

Thanks,

Yes, all SS Camaros are

Leadsled · 03-01-2024, 10:58 AM

Quote:

Originally Posted by bsn

The first thing I would do is run 93 if you can get it, if not 91. 87 is an absolute no-no when your doing any type of performance driving. Second thing is NEVER do any performance driving with an empty tank, your sucking air and running lean and overheating your fuel pump, leading to burnt pistons and failed fuel pumps.

THIS!

redcoats1976 · 03-02-2024, 07:22 AM

i can see why it would be shuddering and shaking at 135 running 87 octane,lucky if it hasnt been damaged by that.

RoadRunner70 · 03-02-2024, 10:42 AM

Quote:

Originally Posted by gtstorey

What is fuel pressure when having the problem. Fuel pressure at idle doesn't mean much when the problem is WOT.

Thank you for reply, I will check it next time.

What is the good readings regarding fuel pressure and flow rate ? Maybe I installed the defective fuel pump ) I found one SPECTRA PREMIUM SP6681M with min flow rate 80 Gph and 75-85 psi

RoadRunner70 · 03-02-2024, 10:46 AM

Quote:

Originally Posted by bsn

The first thing I would do is run 93 if you can get it, if not 91. 87 is an absolute no-no when your doing any type of performance driving. Second thing is NEVER do any performance driving with an empty tank, your sucking air and running lean and overheating your fuel pump, leading to burnt pistons and failed fuel pumps.

I would be glad, but I live in such a hole that there is nothing nearby except 87 gasoline. I tried adding 0,5 gal 99% isopropanol but didn't see any difference.

03-01-2024, 02:07 AM	#1
RoadRunner70 Drives: Chevy Camaro SS 2012 Auto/TR Join Date: Dec 2022 Location: Gisela, Arizona Posts: 56	SS doesn't accelerate more than 135 2011 Camaro SS auto/t, stock. Installed hubcentric wheel spacers. Mileage 121.000, gasoline 87, This is not the first time I have noticed this. When approaching about 135 mph, noticeable vibrations and shaking begins. Looks like the car doesn't want to go faster than 135 mph, acceleration becomes very sluggish. Tranny in S mode and stabilitrak in competitive mode. Previously I drove up to 155 mph without problems. Maybe this is related, not sure. The fuel pump was replaced several months ago with the original one GM MU1959. When fuel level is low (about 40 miles) the car starts to drive poorly and the traction disappears. Or sometimes it throws CEL related to the fuel pressure sensor or fuel control module. After refueling defect dissapears. Idle fuel pressure is 3,9 bar per OBD readings. Any suggestions?)) Last edited by RoadRunner70; 03-01-2024 at 03:17 AM.

03-01-2024, 09:18 AM	#6
Moto-Mojo Fast Cars and Old Guitars Drives: 2015 2SS RS (L99, baby!) Join Date: Apr 2012 Location: N. CA Posts: 3,973	Must be running that Pemex fuel while doing top speed runs in, "Mexico", huh? __________________ “I don’t want to belong to any club that would have me as a member.” - Groucho Marx

03-01-2024, 09:55 AM	#7
ZED SLED Drives: 2017 Mosaic Bk ZL1 M6 Join Date: Jul 2009 Location: South of Raleigh, NC Posts: 9,477 View My Garage	Furthermore, once you've ran 87 in the early 5th gen SS, due to a software glitch you are stuck on the low octane fuel table and the only way to get back on the upper is to do the 5 & 20 fuse pull. IDK, they may have never fixed that for any model year 5th gen. Even made a sticky for this issue https://www.camaro5.com/forums/showthread.php?t=38964 __________________

03-01-2024, 04:28 AM	#2
bsn Drives: 2013 ZL1 Join Date: Sep 2021 Location: Virginia Posts: 301	The first thing I would do is run 93 if you can get it, if not 91. 87 is an absolute no-no when your doing any type of performance driving. Second thing is NEVER do any performance driving with an empty tank, your sucking air and running lean and overheating your fuel pump, leading to burnt pistons and failed fuel pumps.

03-01-2024, 07:50 AM	#4
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,155	What is fuel pressure when having the problem. Fuel pressure at idle doesn't mean much when the problem is WOT.

03-02-2024, 07:22 AM	#12
redcoats1976 Drives: LT W/2LT,blue metallic Join Date: Jul 2016 Location: central florida Posts: 4,915	i can see why it would be shuddering and shaking at 135 running 87 octane,lucky if it hasnt been damaged by that.