Has happened 2 times in past year, 3 times in last month - >50% power loss in the upper RPM range - power comes back after car off and cooled down. First two times were in hot, humid conditions, but the last two times were in cool, dry weather. First two times were when I was pushing the car (first time while on a road course weekend). Last two times were normal highway driving. Usually I can go from 4k RPM to 6.5k in 3.3s - when car in this low-power mode takes something like 5s.
No codes any time. 2.5L non-SVT - only power mods are KKM and aftermarket exhaust. The IAT sensor is right in the air flow, by the way (hole driller in KKM). Running 'regular' (i.e. low octane) gas.
My suspicion is that the computer is backing off the timing for whatever reason, but I haven't heard of this affecting anyone else (did a search). Any possibility of intermittent vacuum leaks, etc.? Sticky secondaries?
Any ideas?
Thanks in advance.
Eric