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Rough Idle, Lumpy on throttle load

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Old 05-25-2017, 12:33 PM
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Default Rough Idle, Lumpy on throttle load

MSM decided to not work today. Drove fine last night.

Car has a rough idle. When I rev it up to about 2k rpms in park it'll hold but stumble and drop rpm randomly. When I drive around in 1st gear it seems fine until I give it more throttle then it stumbles. Under any heavy load it'll stumble and sound like a subaru. Not sure if it's running rich or lean, injectors or ignition.

Halp.

Side note, I did fill up with gas yesterday before coming home... possible I got some bad gas?

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Old 05-25-2017, 01:15 PM
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Data logs would help us help you.
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Old 05-25-2017, 01:26 PM
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Originally Posted by bjorno
Data logs would help us help you.
Cute, no logs bro. OEM computer.
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Old 05-25-2017, 02:02 PM
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Originally Posted by Girz0r
in park
You have an auto?
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Old 05-25-2017, 02:21 PM
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Pull and inspect plugs. If nothing conclusive pull wires off one at a time and see which cylinder makes the least difference.
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Old 05-25-2017, 02:26 PM
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Originally Posted by Girz0r
Side note, I did fill up with gas yesterday before coming home... possible I got some bad gas?
Evap problem? does it run any better with the cap off?
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Old 05-25-2017, 02:28 PM
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Did you overfill the tank?

(@Chilicharger665)
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Old 05-25-2017, 02:34 PM
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Originally Posted by sixshooter
Pull and inspect plugs. If nothing conclusive pull wires off one at a time and see which cylinder makes the least difference.
I will check.

Originally Posted by Onyxyth
Evap problem? does it run any better with the cap off?
I'll have to try that, not sure if that'll be it.

Originally Posted by aidandj
Did you overfill the tank?
Nope, only put in 4 1/2 gallons. Went to a friends around the corner and drove home 2 or 3 miles and parked. Started up fine, gave it throttle to pull out and it turned into a subaru.
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Old 05-25-2017, 03:51 PM
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Alrighty, so either an injector is stuck open or the coil is not firing. Running rich.

Pulled a p0302 for cylinder 2 misfire.

I won't be able to inspect plugs until later. I'm going to swap the coil packs and see if I can get it to misfire on another cylinder.
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