Knock at idle

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Headnsouth
Posts: 40
Joined: Fri Nov 07, 2008 10:35 am
Car: 2005 G35

Knock at idle

Postby Headnsouth » Thu Mar 04, 2021 3:32 pm

Replaced spark plugs about 10k ago and a bad cam sensor. 159K miles on my 05 G35. MPG around town is 18.3, I was getting 20 MPG. The vehicle runs great but I do get a knock at idle, it's almost like getting a bumper tap. No codes. Any ideas on what to check? I've always ran 83 octane and never had a problem. :confused:


Headnsouth
Posts: 40
Joined: Fri Nov 07, 2008 10:35 am
Car: 2005 G35

Re: Knock at idle

Postby Headnsouth » Tue Jun 29, 2021 3:57 am

The problem finally showed itself. Intermittent rough idle along with the check engine light. Ran a scan and it was a 305. Swapped coil packs and the code switched to the other cylinder.
Picked up a new coil pack and all is good. :) Gas ⛽ mileage is back at 20.

Headnsouth
Posts: 40
Joined: Fri Nov 07, 2008 10:35 am
Car: 2005 G35

Re: Knock at idle

Postby Headnsouth » Tue Jun 29, 2021 3:58 am

The problem finally showed itself. Intermittent rough idle along with the check engine light. Ran a scan and it was a 305. Swapped coil packs and the code switched to the other cylinder.
Picked up a new coil pack and all is good. :) Gas mileage is back at 20.


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