Car Idle Issue / check engine light / Code P0306

[ChopperGuner117]

I recently started experiencing an issue with my car where it would misfire when boost started to ramp in and then go away.. well it just now started to kind of be a permanent issue. I get a check engine light on when I press the gas pedal and it is a code P0306.. and my car actively misfires at idle. I turned the tune map to 0 but the issue is continuing. Clearing the code temporarily removes the issue. I wanted to see if anyone else has had this issue and what resolved it before I start going off and replacing stuff. My first thought was spark plugs but idk. I was running it on map 3 prior to issue.

JB4 with fuel harness
BMS Intake
Denso plugs gapped at .20
BMS OCC
GFB BOV Kit 5

 

[AYip31]

I recently started experiencing an issue with my car where it would misfire when boost started to ramp in and then go away.. well it just now started to kind of be a permanent issue. I get a check engine light on when I press the gas pedal and it is a code P0306.. and my car actively misfires at idle. I turned the tune map to 0 but the issue is continuing. Clearing the code temporarily removes the issue. I wanted to see if anyone else has had this issue and what resolved it before I start going off and replacing stuff. My first thought was spark plugs but idk. I was running it on map 3 prior to issue.

JB4 with fuel harness
BMS Intake
Denso plugs gapped at .20
BMS OCC
GFB BOV Kit 5

How many miles on them Denso?

 

[ChopperGuner117]

How many miles on them Denso?

Almost 20k

 

[AYip31]

Almost 20k

It’s probably your plugs. From what I’ve heard they only last 10-15k miles.
That’s why I went with HKS

 

[ChopperGuner117]

It’s probably your plugs. From what I’ve heard they only last 10-15k miles.
That’s why I went with HKS

Okay, really appreciate that.. how long the hks good for?

 

[AYip31]

Okay, really appreciate that.. how long the hks good for?

Not sure. But longer the Denso

 

[ChopperGuner117]

Not sure. But longer the Denso

Thats all I need to know!! Thank ya!

 

[Terry@BMS]

Desno normally last around 20k miles, HKS around 30k. We have both on our site.

 

[Aether]

So I have a similar issue. However I just installed my spark plugs in preparation for my tune. It idles rough with both the stock and new ECU and once I get on the throttle it dies down. The rough idling is also very inconsistent. Is the gap bad? I set them each to .025in or could something like an ignition coil been a culprit? The car doesn't even have 7k miles on the clock either so I'm worried that I broke something severe.

 

[cncBilly]

So I have a similar issue. However I just installed my spark plugs in preparation for my tune. It idles rough with both the stock and new ECU and once I get on the throttle it dies down. The rough idling is also very inconsistent. Is the gap bad? I set them each to .025in or could something like an ignition coil been a culprit? The car doesn't even have 7k miles on the clock either so I'm worried that I broke something severe.

What tune?

 

[Aether]

What tune?

I'm running with Lozic, but the issue started before I even put the tune in. Only started happening after I put the new plugs in. Issue doesn't go away if I put the tune in or go back to the stock ECU. Tomorrow I'm bringing it to the shop I used to work for to try and figure out the issue. Check engine light also sometimes comes on and off.

 

[Landboat G80]

I'm running with Lozic, but the issue started before I even put the tune in. Only started happening after I put the new plugs in. Issue doesn't go away if I put the tune in or go back to the stock ECU. Tomorrow I'm bringing it to the shop I used to work for to try and figure out the issue. Check engine light also sometimes comes on and off.

Lozic recommend 0.028 HKS
Make sure your Coils/O2 are plugged in well

 

[desmorider804]

Any followups for above issues?