Hi,
The idea that it happens when you install the air filter housing leads me to believe the fuel mixture is already too rich and the filter assembly is just enough to cause the issue.
The first thing I suggest is to check the fuel pressure to confirm the regulator is doing it's job. Here is a link that shows how to test pressure. You will need a fuel pressure gauge, but most parts stores will lend you one.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
I attached the manufacturer's fuel pressure specifications below (pic 1).
Also, the regulator/pulse regulator is under the intake. See pic 2. Disconnect the vacuum hose to it and see if there is fuel in the hose. Also, pay attention if the fuel pressure changes when you disconnect it. You may not be able to disconnect it without removing the intake, but follow it to where it attaches at the intake and disconnect it there.
Let me know what you find or if you have other questions. Also, let me know if you have a live data scan tool. If you do, I need you to check two things. First, while the engine is running, check the short-term fuel trims. Also, when the engine is cold, before starting, see what the coolant temperature sensor signals. It should be very close to ambient temperature.
Take care,
Joe
See pics below.
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Tuesday, August 17th, 2021 AT 9:08 PM