Help: Irregular cold start throttle surge
New to the forums. Traded in my 3.7 in March and brought home a 13 GT with 10,000 miles on it. It's my baby, and I love to take care of my things. Naturally, every noise it makes or irregular feeling it gives me I obsess over and investigate. I want to know that it is performing as intended and firing on all eight.
As the title states, I'm getting an unusual throttle surge after a cold start. Going into further detail, I want to clarify that I know on a cold start the throttle surges to around 1,100 and drops as the car warms up. I know this is normal operation. What I'm experiencing started about 3 weeks after I brought the car home. After cold starting the car in the morning or whenever it has been stationary for hours, the slightest touch of the throttle revs the car very quickly. The strange thing about this is the way that it revs. It shakes the car, and then the revs drop down to operating temp right away before climbing back to warming revs. Why would that small rev shake the engine? The irregular rev only goes up to about 2,000 but it neither feels or sounds smooth.
The car will do this only within a 15 second or so window after a cold start. After the revs drop to about 900 then it will rev normal and I will be on my way. So now I always wait about 30 seconds after a cold start, which is probably a good idea to do in any any car. But I've never had to do that in any other car I've owned, including the 2011 3.7.
I feel like the system is reacting to the internals not yet being well oiled. Oil level is perfect and I run royal purple synthetic. I also have a k&n cai and axelbacks.
Other than the usual mt82 and clutch racquet the car runs amazing. Very curious, has anyone experienced this before?