A year ago I bought a new fpr supposedly OEM specs for 155AUD and installed it. At the time i had some idling and engine losing power issues. Anyway I replaced the injectors on my 300zx tt with a set of new old style ones. On start up all was fine the hiccup at idle was gone, all good, however I noticed the crank time was still long, had to crank it maybe 2 or 3 times to start. Also noticed a dead spot when cold, after warming up it went really well. I parked the car for 3 hours and I had a no start, coaxed the engine into firing, it stumbled after that it went ok. Checked the fuel pressure...idle 34psi and 39psi opening the throttle...hmmm Shut engine off and fuel pressure fell straight to about 5psi, then zero... Fuel pump is new, fuel is clean. The new fpr had no leaks and no fuel in the vacuum hose... Clamped the return line and pressure was holding...released the clamp and pressure down to zero. So no leaky injector..good Replaced the fpr with the original 30 year old one and fixed the problem. Now 37.7psi idle and 43psi opening throttle. ..and yes my gauge is accurate. System holding pressure now over night. Car starts now straight away, no more flat spot... Lesson learned never buy unbranded 'OEM' replacement parts..made in China and sold in Oz for a 500% mark up.