I have had this issue for quite some time since the HSR swap, but since the car is being sold, I want to get rid of it (it is the only thing holding this car back from being close to perfect). Anyways, when it is the first start of the day, it will start right up, but will die shortly after unless you press the gas and hold it up at a fairly high RPM (2500-3000 rpm) and let it warm up for a couple of minutes. After that, the car will run just great for the remainder of the day. The weird thing is that when gas is given in a quick manner, such as accelerating and revving it up high, it wants to die. This is only on the cold start. I checked codes and got codes for the MAP, EGR, temp sensor, and EST. Any suggestions as to what is causing this?

 

Have you done any other modifications to the motor, and has the ECM been setup for it?

 

Just HSR and exhaust. No internal modifications. I am still running a relatively stock tune. I've heard of people getting away with the stock tune with minimal problems, but of course is not the ideal set up. It is just odd that I am getting all of those codes and the car runs great when warmed up, but that first start of the day is real puzzling.

 

Any ideas? I saw very similar problems posted before, but no real answers.