ok yea it didnt throw and lights or codes
It may or may not throw a code because the imputs (EOT, and IAT) are a little out of wack, you could have bad sensor on either of these two, or an intermittently bad sensor on the two and still not throw a code. Since those are the only two sensors that tell the EBPV to cycle on (which is what it did in your case) that would point to one of those two acting up.
I had a bad Exhaust Back Pressure Senor (EBPS) that was bad and it stored the code in the PCM but didn't throw a light, don't get confused the EBPS does not have anything to do with the EPBV cycling on, it is another imput to the PCM which controls when the EPBV will cycle off.
Here's how it works.
IAT is Below 37 degrees (50 degrees some models)
EOT is Below 140 Degrees (168 degrees some models)
Then the EBPV will cycle on. Note Both parameters have to be met, When it's 70 degrees out(in your situation) and your engine is cold, the IAT parameter is NOT met, but the EOT parameter is met ( your oil temp will be equal to 70 degree ambient temp on a cold engine) Both Parameters have to be met
Now with the EBPV on, and you hit the throttle depending on the load the PCM will kick the EBPV off so you have normal power of the motor, it does this by monitoring the input of the Exhaust Back Pressure Sensor (EBPS), the more you hit the throttle the more load you want, hence the Exhaust pressure goes up and the PCM kits off the EBPV to allow you to maintain that load.
Long story short your PCM saw both Parameters (IAT and EOT) were met based on what the sensors were telling it, so one of the sensors is probably acted up.
Make sense to you?
If it doesn't come on again at below 70 or 50 or 37 I wouldn't worry about it, it comes back I would be willing to bet the IAT sensor is the problem