Misfire, rough idle, shuts off when stopped and engine light is on

1999 HOLDEN CALAIS
20,800 MILES • 5.7L • V8 • 2WD • MANUAL
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ASH THOMPSON
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  • 2 POSTS
VT clubsport LS1. Has rough idle, struggles at low rpm and then a bit of power suddenly kicks in as the rpm gets higher and it shuts off when I stop at a corner and blows black smoke when you open it up, engine light is on too.

I have replaced the coils, leads and fuel pump and I cleaned the throttle body and sensors.
Jul 6, 2020 at 9:12 PM
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KASEKENNY
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Black smoke, rough idle, and low power are symptoms of over fueling. Unfortunately we don't have a manual on this vehicle to help determine the root cause because this vehicle is not offered in the USA.

Here is a guide that talks about black smoke. We need to run through this and start looking at the fuel system.

https://www.2carpros.com/articles/engine-black-smoke
Jul 7, 2020 at 2:43 PM
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ASH THOMPSON
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Okay, yeh I got a new MAF sensor and spark plugs and it's still the same, I'll try injectors next. It's got an engine light on but the scan tool says there's no fault codes on the vehicle.
Jul 8, 2020 at 7:56 AM
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KASEKENNY
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  • 18,907 POSTS
Okay. I would suggest checking the fuel pressure and then testing the injectors. This will not tell if they are leaking so I understand if you are going to just replace them. Let us know what happens.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-test-a-fuel-injector
Jul 8, 2020 at 8:22 PM