Car shaking and losing power under medium/hard acceleration - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Myke783 · 05-19-2021, 05:06 PM

Hello,

Was curious if I could get some input on a problem I've been chasing for months.

My car tends to have a low end hum/vibration when I go to accelerate from a stop. It will normally level out at around 40mph. However, If I barely accelerate and keep the rpms low (under 1500), I dont get the problem. There's also a huge loss in power, almost feels like my car is slipping the whole time. My exhaust makes a horrible fluttering sound. It also occurs everytime I make a left turn even when babying it. Also gets way worse once car is warmed up.

I've already spent thousands at the dealership, and they swore up and down it was my trans lines leaking and low fluid.
(This after having them install a new transmision 2 years prior)

I did notice my 7 and 8 spark plugs had a little fuel on them.
So I replaced all 8, the plug wires, and just recently put on 8 Accel Coil Packs. And the problem is still occurring.
Im really hoping it's not a leaky Fuel Injector. Maybe ones clogged.

My car is not throwing any codes..

I've also replaced my cai air filter, checked for vacuum leaks, my MAF & O2 sensors seem fine. Dont believe I have an exhaust leak.

Also might be paranoid but pretty positive when I'm in 5th gear at a constant pedal, my rpms are slightly going up and down making a hum. I've also had my rpms jump when accelerating smoothly.
Which leads me back to the injectors.

More than happy for any input you guys may have.

Thanks!

Avenging Orange · 05-19-2021, 05:20 PM

How old is battery? What plugs and what gap? How many miles? Other mods?

Myke783 · 05-19-2021, 05:48 PM

The Battery is about 2 years old. Car never has problems cranking, even with those 2 wet spark plugs.

The spark plugs are AC Delco, .040 gap.
Just over 128,000 miles.

Mods include AR long tube headers, hi flo cats, borla atak exhaust, volant cai. It has a diablosport can tune, with the injector slope slightly adjusted for the headers.

With the last shop visit, I had both trans cooling lines replaced, new gas tank, fuel pump, and fuel level sensors, 2 O2 sensors replaced, new wiring harness and a new ac compressor installed.
They informed me the trans lines and low fluid is what caused the fluttering and shaking. I called bullshit since they replaced the whole transmission and torque converter 2 years prior. (Lost 5 & 6 gear and reverse on the old trans)

spyderbuddy · 05-19-2021, 07:39 PM

I just had the catalyst replaced

Avenging Orange · 05-20-2021, 10:45 AM

Hmmm. I know when I replaced plugs it ran like crap when gapped at .040. I had to go to .035. But that's just me.
I agree on the B.S. ref trans fluid.
Also know some have had issues with aftermarket coil packs.
Have you tried switching around coils to see if it's the same cylinders......or tried putting stock coils back on?
I'm sure you have worked all angles...im Just spit balling here. Good luck.

05-19-2021, 05:06 PM	#1
Myke783 Drives: 2010 Camaro 2SS/RS Join Date: Mar 2011 Location: the woodlands, tx Posts: 13 View My Garage	Car shaking and losing power under medium/hard acceleration Hello, Was curious if I could get some input on a problem I've been chasing for months. My car tends to have a low end hum/vibration when I go to accelerate from a stop. It will normally level out at around 40mph. However, If I barely accelerate and keep the rpms low (under 1500), I dont get the problem. There's also a huge loss in power, almost feels like my car is slipping the whole time. My exhaust makes a horrible fluttering sound. It also occurs everytime I make a left turn even when babying it. Also gets way worse once car is warmed up. I've already spent thousands at the dealership, and they swore up and down it was my trans lines leaking and low fluid. (This after having them install a new transmision 2 years prior) I did notice my 7 and 8 spark plugs had a little fuel on them. So I replaced all 8, the plug wires, and just recently put on 8 Accel Coil Packs. And the problem is still occurring. Im really hoping it's not a leaky Fuel Injector. Maybe ones clogged. My car is not throwing any codes.. I've also replaced my cai air filter, checked for vacuum leaks, my MAF & O2 sensors seem fine. Dont believe I have an exhaust leak. Also might be paranoid but pretty positive when I'm in 5th gear at a constant pedal, my rpms are slightly going up and down making a hum. I've also had my rpms jump when accelerating smoothly. Which leads me back to the injectors. More than happy for any input you guys may have. Thanks!

05-19-2021, 05:20 PM	#2
Avenging Orange Drives: 2010 Inferno Orange 2SS/RS Join Date: Apr 2010 Location: Clermont, IN Posts: 3,297	How old is battery? What plugs and what gap? How many miles? Other mods? __________________ 2010 Inferno Orange 2SS/RS M6 Black Leather, Sun Roof, OBX Headers, Borla touring axle back, Cold Air Inductions CAI , non synthetic fluids, BMR total bushing upgrade/1" lowering springs, DSE 32mm rear sway bar. GM fe4 shocks/struts/LCA's, AAM 3.91 diff, Vertini RFS1.8 20x9 +30. Conti ExtremeContact Sport 275/35/20. sjm autoprod ABL dash kit. Mike Norris tuned 413/419. Avenging Orange: 43 years of not buying into the Hype........and damn proud of it!! https://youtu.be/9JD9it6SmB8 https://youtu.be/xmelTlEzI34 KICKING CANCERS ASS SINCE 2015!!

05-19-2021, 07:39 PM	#4
spyderbuddy Drives: 2010 RS Inferno Orange Metallic Join Date: Mar 2010 Location: Albany, Ga. Posts: 3,398 View My Garage	I just had the catalyst replaced __________________ PCP Hideaway Headlight Covers, BBK Headers & High Flow Cats, ZL1 Add-ons Wicker Bill, TL1/ZL1 Hood Insert, Gen5 DIY Frameless Mirror, ABL Dash Lighting an My link Navigation, Blacked out Rear Bowtie, all Sylvania led Turn Signals, Ceramic Window Tint By Nicks, MBRP Exhaust tips, GEN5 DIY Virginia Legal DRL Harness, Painted Brake Calipers, Vittesse Throttle Controller, Heritage Grill, Diode Dynamics Led Lighting, Manual Shifter Boot, Paddle Shifters, CNC Throttle Body, Trifecta Tune, RX Catch Can & Breather, Trunk Black out and Side Grills, Chevorlet door Sills.

05-20-2021, 10:45 AM	#5
Avenging Orange Drives: 2010 Inferno Orange 2SS/RS Join Date: Apr 2010 Location: Clermont, IN Posts: 3,297	Hmmm. I know when I replaced plugs it ran like crap when gapped at .040. I had to go to .035. But that's just me. I agree on the B.S. ref trans fluid. Also know some have had issues with aftermarket coil packs. Have you tried switching around coils to see if it's the same cylinders......or tried putting stock coils back on? I'm sure you have worked all angles...im Just spit balling here. Good luck. __________________ 2010 Inferno Orange 2SS/RS M6 Black Leather, Sun Roof, OBX Headers, Borla touring axle back, Cold Air Inductions CAI , non synthetic fluids, BMR total bushing upgrade/1" lowering springs, DSE 32mm rear sway bar. GM fe4 shocks/struts/LCA's, AAM 3.91 diff, Vertini RFS1.8 20x9 +30. Conti ExtremeContact Sport 275/35/20. sjm autoprod ABL dash kit. Mike Norris tuned 413/419. Avenging Orange: 43 years of not buying into the Hype........and damn proud of it!! https://youtu.be/9JD9it6SmB8 https://youtu.be/xmelTlEzI34 KICKING CANCERS ASS SINCE 2015!!

05-19-2021, 05:48 PM	#3
Myke783 Drives: 2010 Camaro 2SS/RS Join Date: Mar 2011 Location: the woodlands, tx Posts: 13 View My Garage	The Battery is about 2 years old. Car never has problems cranking, even with those 2 wet spark plugs. The spark plugs are AC Delco, .040 gap. Just over 128,000 miles. Mods include AR long tube headers, hi flo cats, borla atak exhaust, volant cai. It has a diablosport can tune, with the injector slope slightly adjusted for the headers. With the last shop visit, I had both trans cooling lines replaced, new gas tank, fuel pump, and fuel level sensors, 2 O2 sensors replaced, new wiring harness and a new ac compressor installed. They informed me the trans lines and low fluid is what caused the fluttering and shaking. I called bullshit since they replaced the whole transmission and torque converter 2 years prior. (Lost 5 & 6 gear and reverse on the old trans)