Z & ZX fuel injectors

[sideshowbob]

I recently had a fuel injector die out on me on my 77 280z and replaced it with one I pulled from a n/a ZX in the junkyard some time before. It went in an unusual way.. When I pulled the plug to the cylinder at idle, the engine roughened as expected but when I pulled the injector plug there was no change (injector leaking?). Now that I've replaced it the engine runs more smoothly (still rough) but removing the oil filler cap no longer causes it to die. So.... did I fix the problem and now have a vacuum leak to trace or is that single injector putting out way too much fuel? Victoria british lists the same part number for the injector, however the ZX injector has no 'cup' on it's tip (the ones on my Z are NOT removable and are molded to the main tip). Anyone??? Are these the same? Before this I was also running VERY low vacuum (11in/hg) and haven't gotten around to checking it again.

Oh, and I'm having serious trouble shutting my valve train up. The PO installed chrome molly springs with a reground cam, would this increase the noise?

[First Gen Z]

Rocker arm noise is relative to valve clearance. Check the clearance to see if it corresponds with the cam grinders specs. The cam could be the cause of your low vacuum at idle.

[sideshowbob]

Rocker arm noise is relative to valve clearance. Check the clearance to see if it corresponds with the cam grinders specs. The cam could be the cause of your low vacuum at idle.

Certainly, the problem is that I don't know who ground the cam. While the low vacuum could be partially caused by misadjusted valves, this low a reading points to something else as well. Is there any way to check for a jumped timing chain without removing the front cover? I have already adjusted the chain for stretch to the #2 position, btw. Also I may have failed to mmention that the car had a steady 14 before some of these problems occurred. Now a fluctuating 11-12 inches (just checked it again post-injector replacement). The car has a definite change in idle when unplugging #3 now. On a side note, I thought my new (well, new to me) injector was also faulty because I had placed the injector in a position where the connector would not seat due to the screws holding the assembly down Then the number one injector got loose (clips are off right now) causing me a headache until I figured it out. Whata morning!

Oh, and at last check the compression (cold!) is as follows:

Compression Test Wednesday, June 08, 2005

Some cylinders take all 7 strokes to reach full pressure

160

160

165

165

160

170