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New(er) to LS engines and troubleshooting is my weak area still.
I have an LQ4
trick flow GenX220 fast as cast heads.
Yella Terra YT6645 roller rockers
Howards cam model 196765-12
228/234 @.05"
.604/.609" lift.
112 lobe seperation
108 intake centerline
LS6 intake
36lb Fast 303608 injectors
Hooker Super Competition Headers 2201
New Wiring specialties LSx wire harness
Setup as Speed Density
My idle is rough'ish fluctuating between 725-800RPMs. I have a P0200 injector circuit malfunctioning. My manifold pressure is also fluctuating 7-8lbs. there are no cylinder misfire codes
My thoughts are a leaking intake manifold gasket for the low manifold pressure. The Injectors are new and not sure how to test the injectors. Its a delphi harness with adapters between harness plug and injectors. was also thinking to go and get NOID light to test the harness through the adapter. not sure its necessary as I have no engine misfire codes. should I still do this step? tomorrow moring I also plan on taking my can of starter fluid and spray all vacuum hoses to detect for idle change (leaks).
What am I missing, or any suggestions? I am almost shooting in the dark here.
Picture of my car and engine added. thank you in advance.
If you suspect a manifold vacuum leak I would address that first. Pull the manifold and check all the O-rings. If suspected, put in new ones. Cheap insurance.