P0300 on Highway cruise
#1
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Hi guys having an odd issue I just got my ls6 swap finished and tuned by frost (who did a great job) and I'm getting a p0300 code on the hwy only. If i drive around town everything is fine but the minute I get on the hwy I will start getting a flashing ses light but it isnt detectable in the car the engine seems to be running fine in fact after I get off the hwy the light will go off and not come back on until next time. The first things I'm going to check are plugs and wires but being it isnt set off in town I'm not sure if it can be that? I'm going to try and do a iac relearn tomorrow per the instructions frost sent me just in case it didnt work well the first time and I'm going to be borrowing a buddies scanner tomorrow to look at the long term fuel trims just wondering if anyone here had something to add. The car does have a small exhaust leak that I'm working on getting fixed but its at the collector and I'm not throwing any o2 codes so I think its ok there.