suspicion of vacuum leak wrong? need of assistance

[neetyrom]

Happy holidays everyone,
So i replaced the inner and out fuel injector seals and the corresponding fuel rail hoses, as well as all the intake gaskets and sealed with permatex copper manifold sealent. Now when i go to start the engine it abruptly starts on the first or two cranks and then dies out. To add to this, I hear a noise coming from the fuel pump that remains on when i put the car in ACC. the fuel pressure regulator seems to be making a leaking noise, similar to the noise you hear from a leak in a bicycle tire.
Im definitely starting to think their is a problem in the fuel delivery system, I dont know where to start. I have a suspicion its the relay, but since the fuel pump makes that whining noise this disapproves it correct? any assistance is great thanks gents.

[Mike W.]

Vacuum leak would be my first thought. The pump is switched by the combo relay, an odd one, but should only run with the engine cranking or running, not just with the key on. While I've never noticed it, a sound at the FPR wouldn't be unusual since the pump runs full once it's energized and the FPR is really a pressure relief device, allowing excess fuel/pressure to bypass back to the tank.

Check all the intake areas again, a gasket may have slipped out of place on assembly.

[neetyrom]

this might as well be the case, when lining up the gasket with the cylinder how does one know the seal is properly secure, and should I tighten all the nuts little by little switching in between them or should I just tighten them one at a time? what do you think?

[RonDwyer]

first off, with new gaskets don't use sealant. Excess will burn and poison your O2 sensor. The proper feel of torque by hand is a learned skill.

[neetyrom]

had my buddy who works on e30s come over and look at it, no vacuum leak, fuel pressure regulator and fuel pump all work fine, including the relay, we narrowed it down to the wiring harness that is connected to the ignition coil. For some reason, the voltage supplying the coil directly from the battery (we bypassed the battery) was 12 from the large nut and 3 from the small nut, and 12 from the tower. Ideally you want anything from about 12-14 on each, but the small side is loosing voltage somehow and therefore not generating enough spark to the engine. We could be on to something here, any input is greatly appreciated.

[neetyrom]

So weeks later and i fell obliged to tell the gents on the forum the problem is fixed. After getting ripped off by 2 highly reputable guys and chalking up the board back to square one the problem was finally traced back to a crack in the rotor cap. This caused a failure to send current/ voltage to two of the spark plugs and prevented the engine from firing correctly.
-Ciao

[RonDwyer]

Really? You found the issue among all the deferred maintenance?

[neetyrom]

.....no deferred maintenance over here Ron..... just a lot of patience, commitment and connections.
Peace & best wishes