I have a 5.3 in my Camaro and have recently been experiencing a strange cold start issue. On a cold start the engine is bogging pretty bad when you blip the throttle. If you mash the throttle, or even under a light acceleration in gear, it boggs like a carb'd engine would that is flooded. When I hit the throttle, the RPM drops slightly then very sluggishly begins to climb and seems to catch up to itself around 3k RPM. It does this almost every cold start (its around 70 degrees in my shop), but it has not always done it. I have had the car tuned for about 3 years and it has only been having this issue the past few months. Nothing has changed in the tune, no CEL or codes, no changes to anything. My fuel pressure is rock solid at 60, no voltage drops, etc. I will attach the log showing startup and some throttle blips, and also the tune. I am going to upload a video of it as well and post the link.
Another issue I have had since day one which I am wondering if anyone has an answer to but is not as important, is it always takes me hitting the key twice to get the engine to fire immediately. If I turn on the key and let the pump build pressure (I have my pump always on with key) and hit the ignition it will turn over a lot and finally stumble to life. If I hit the key for half a second, go back to "on" and then hit the key again it fires immediately with no problems. Again, this issue has been since day 1 and the bogging just started. I just wanted to see if someone could help me out with one, or both issues.
Thanks!
03 5.3 W/4.8 pistons T56 MT
224R texas speed cam
Holley victor style intake with TB
Holley 36lb injectors
no MAF
Long Tubes