# 2005 GTO LQ9 block with 243 head



## Joecericola (Jul 19, 2021)

I just purchased an 05 and the previous owner swapped an LQ9 block and kept the 243 head from the LS2. About 15 minutes after purchasing the vehicle I got on the highway and the check engine light started flashing. I pulled over to scan the code and it was for a random misfire, but the vehicle doesn’t seem to be misfiring at all. The previous owner said it needs to be taken to GM for a “case variation relearn” to set the timing correct. Has anyone had a similar issue? Or should I expect something more serious?


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