I just put a direct port nitrous kit on my car, i bought the kit off of a friend with manifold already. when i put the kit on the fuel pressure was high so i went to turn it down and it wouldnt go lower then 45psi. I checked for leaks and didnt find anything so i thought it was the gauge or regulator. Ive changed both and still no different. Ive also replaced the fuel filter. Ive read that it could be the return line but its weird that as soon as i put the different manifold on is when i start having problems and never had these problems before. I also thought that it could be from the kit but i took the fuel line for the nitrous kit off the fitting where the gauge reads and it still is the same. Let me know what you guys think i should check or try next. thanks.

 

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