Update on Pcm codes 0300 & 0106

[vettekingz06]

Hi to all---A month ago i needed help with these codes on my 2003 Z06 and got some responce. I have found my problem to be a broken exhaust valve spring on cyl 2. By luck it didn't drop the valve down in the cyl. and it looks as though i will be able to repair it with a new spring. The car only has 7000 miles and has not been driven hard. When we looked at the misfires (code 0300) cyl. 2 had the most misfires ( 120), with other cyl.s ( 3 and 8) having 4 or 5. It was making a very slight ticking sound but not enough to suspect a broken spring. I thought i had a vacuum leak and looked for that to no avail and then started to look at the random misfires. I hope this will help someone find this allusive trouble.

 

[gmjunkie]

I remember that thread!!! But you know my LS 6 in my Olga Car Hauler did that!! Not the codes,but broke a valve spring!! It was weird too,I ran down the vacuum and plug wires 5-6 times and then pulled the valve cover #1 bank and found #5 exhaust spring broken!!I'd swore it was a vacuum leak,I only had about 9-10,000 miles on the heads,I'm purdy Lucky I didn't drop a valve though,I was on my way to Florida to pick up a Couple Vette's I'd bought while I was down at the Old Town Show last year!! It wouldn't miss above 17-1800 so I kept on Truck'n it the rest of the way down there and Hauled 2 cars back with it and still got 9 MPG!!