AZRob67Camaro

Recent weeks have experienced hard start after several hours of sitting. The problem has seemed to progress to the point of not starting at all. I've replaced fuel pump and filter, thinking it was not getting enough pressure to start vehicle. Relay seems to work as I can hear pump coming on. Spark is there at the plugs. Compression doesn't seem to the problem, because after finally starting it runs great with no issues. Can go somewhere and shut down for an hour or two with no starting issue. I pulled intake manifold top half to get a look at the regulator. Should I replace injector and regulator? What about fuel inlet hoses(nut kit?)? I would prefer not buying a new injector unless there is a good possibility this is the issue. Any suggestions?
P.S. I did not reinstall the pulsator in the fuel line as the new pump did not come with one - is this going to be a problem? What the bleep is a pulsinator?

Chris Stewart

With the intake top still off, turn the keyswitch on and look for gasoline leaking from the regulator & fuel lines.

MT-2500

And check the fuel pressure for up to par.
Many after market fuel pumps do not have good pressure.
What kind of pump did you use?
Did you put extra gas in tank after pump replacement?
The pulsinatator is a fuel pressure cushion or damper.
Did you old pump have one and did you reinstall it or just bypass and leave it off.

Post back your fuel pressure reading.
And as Chris said look for leaks in there.
And check for a fast leak down on fuel pressure.
MT

__________________
Remember proper testing gives us the answer to many problems.
MT

AZRob67Camaro

I have already removed the CPI unit including the "spider" assy. There was some fluid in the top of the manifold, so I suspect some leakage either in the unit or the lines into or out of CPI. I was careful to not break any of the very brittle lines and poppets, but suspect replacement is a worthwhile endeavor. I have located the complete unit online for $300.00 including the inlet lines, spider lines and gasket. The new fuel pump was from AutoZone and was supposed to be direct replacement. With CPI out of the loop I cannot test fuel pressure. I have been informed by a mechanic that the pulsator is not critical(in fact may be better without it) to maintain pressure. Thanks for your quick response and advice. Perhaps I can check pressure at the inlet to manifold. The fuel tank is full. and I left the pulsator off and used the direct tubing provided by the pump manufacturer.

MT-2500

If you are replacing the spider unit make sure you install a new line/nut kit.

And check for leakage and leak down and pressure before installing intake.

Unless the AZ fuel pump was a AC-Delco/Delphi OEM type fuel pump you are not out of the woods on the fuel pump.
Airtex and Carter fuel pumps are junk any more.
Always check all fuel pump pressures.

As said the pulsator is only a pressure cushion/dammper.
It will work with or without it.
MT

__________________
Remember proper testing gives us the answer to many problems.
MT