[Juiced1]

Change your plugs and make sure you battery has a good charge. Also, and I can't stress this enough....If your spark plug wires have been off a few times and aren't clicking back on the plugs good it might be time for a new set.



Are you in Berwyn IL? If so you should swing in for a bit and I can scan your car and see if you do have a misfire or not.

[NITEMER]

So it sat all 4th of July weekend and when I started it Sunday night all the same fault codes came back. I will go back to 100% stock. I started getting these issues long after I had installed the TB and a week or so before I installed the RotoFab. The coils had never been removed till last weekend when I swapped Cylinder 1 and cylinder 2 coil packs to see if the misfire would follow the coil and it didnt misfire detected on cylinder 1 again and also "random misfire code". I will install all new plugs this week.

The spark plug did not look cracked in person but yes it sort of looks cracked in the picture.

Juiced1 I am in Berwyn and was just in St Charles this past weekend. I can Take the car your way at your earliest convenience.

[Revalot]

Where/when did you get your last tank of gas ? And if someone else drove it maybe they put regular in the tank, or a tank of 90-93 might have had water in it !

[NITEMER]

The car has been thru about 3 tanks of gas since this all started, I'm the only one that drives it.

[NITEMER]

Update 7/20

Dealer just called me and confirmed cylinder misfire and said injectors 1-3-5-7 need to be replaced and some fuel line. They said it would be about $2K.......

When I scanned the car before I took it in i could only see cylinder 1 misfire so I swapped coils #1 and #2 to see if the misfire followed the coil and it did not misfire continued in cylinder #1.

My car is out of bumper to bumper but has powertrain warranty, injectors fall under bumper to bumper and not powertrain. BS


And they said injectors are on back-order for about 4 weeks.

I have a case # with GM and will see what they say, car only has 29k miles.

Thinking I will do the work my self, these injectors are about $80 each.

[joeyazzata29]

ive had p0300 only on the race track, I have history codes C0242, U0401 U042B like yours, did this fix your problem?

[zain]

I would change plugs before doing anything

[joeyazzata29]

Originally Posted by zain

I would change plugs before doing anything

Been thinking this but even on a 2021 with 7k miles?

[joeyazzata29]

Originally Posted by zain

I would change plugs before doing anything

And mines only on the race track but idle is a bit rough, could plugs only cause p0300 on the track if it’s a minor fault or crack?

[zain]

Originally Posted by joeyazzata29

Been thinking this but even on a 2021 with 7k miles?

In your case, I would let the dealer have a look first! have you done any modifications?

[joeyazzata29]

Originally Posted by zain

In your case, I would let the dealer have a look first! have you done any modifications?

Stock, dealer had it for 5 days found nothing wrong

[zain]

Originally Posted by joeyazzata29

Stock, dealer had it for 5 days found nothing wrong

Could be bad gas. Have you used any fuel injector cleaners?

[joeyazzata29]

Originally Posted by zain

Could be bad gas. Have you used any fuel injector cleaners?

I haven't, CPO w 7k miles

did it on track twice 05/02 only in left turns less than 1/4 tank or so

no issues on track 05/07

no issues til on track again 06/22, again, left turn, 1/4 tank or less, same thing

Fuel starvation?

[gtfoxy]

I thought I remember reading about some fuel starvation issues with low fuel tank volume.

May want to search the road course section.