was sitting at about 42 psi with the key in the on position, then after i started the car it went to abuot 32-33 on idle and maybe 35 on about 2000rpm+..

could this be a problem? car is having some drivability issues, it will stumble frequently. o2's needed replaced so i did that now im just doing some tune up, changed my plugs and doing wires next. old plugs looked decent actually, were tan and looked even with ever cylinder

 

Camaro350z28:
Your numbers sound normal. The 41-45 fuel pressure spec is a differential pressure number (DP). With the engine off, 42 psig is ok and running at idle the DP is the difference between the fuel rail and the manifold vacuum or your 32 psig minus about 10 psia of vacuum or still 42psig DP.

 

Your fuel pressure is not normal. You should have 43.5 psi both at idle and at WOT. However, you have to measure it with the vacuum line unhooked and plugged.

For a little help refer to Shoebox's website: http://shbox.com/1/4th_gen_tech2.htm...essure_testing

 

I agree your fuel pressure is low with engine running..

 

Just to clarify, you will not have 43.5psi at idle with the fuel pressure regulator vacuum hose attached, it will be less depending on how much vacuum.
If you unplug the vacuum line (or go WOT) the regulator will see atmospheric pressure, and hold 43.5psi.

Unplug the vac hose and test your pressure again at idle.

 

ya well im an idiot. ive done this plenty of times before and still dont learn. forgot to pull off my vacuum line

sorry for the wasted time to you guys but i appreciate the quick answers