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Discussion Starter #1 (Edited)
I did something but I'm not sure what exactly.

1995 Caprice Wagon 200+k Runs great, drives great.

Previous owner installed new fuel pump shortly before I bought it. However, the gauge didn't work properly and it was driving me crazy. Other than that there were no problems. Engine would fire up almost as soon as it started cranking over.

Fast forward 15 months and I bought a new pump/sending unit combo from Spectra. Install was pretty straight forward. Dropped tank, remove old pump assy, cleaned up some dirt that was in tank, install new pump assy. Installed a new Filter, put some gas in tank and start car. Drove to gas station and filled it up with premium.

Turned on the key and gauge stayed at zero. Started car, which took longer than it ever had before. Once started the gauge went to full. Drove home and parked it. The next morning, the trouble started. Turned on key and all seemed fine but the engine turned over several times before it started. Turn off engine and restart, fires right up like normal. So now, every morning it turns over a few times before starting. The other night I didn't think it was going to start at all. So I brought it home and let it sit.

Today I checked the Fuel Pressures. Turn key on and it instantly hits 43PSI. Once the pump stops it drops to 36 before quickly dropping to 0. Started engine (cranked over several times)and it sits at 34PSI, rev it and it goes into the 40s. Pull the nipple off of the FPR, while running, it goes to 43. Shut off engine and pressure quickly drops to zero. Turn key back on and get the same 43/36/drop but the engine will fire right up. Only does the long cranking when I let sit for a little bit.

Did I mess something up during install? New pump assy is garbage? I'm confused. As I said the car was perfectly fine until I changed fuel pump assy.

Sorry for long post but I wanted to give all info. Thanks.
 

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Given you just swapped the pump assembly and these problems shortly followed the new Spectra assembly is suspect...or the wiring to it

Did you put a FP gauge on to see what pressure is when the problems occur?
 

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Discussion Starter #3
Given you just swapped the pump assembly and these problems shortly followed the new Spectra assembly is suspect...or the wiring to it

Did you put a FP gauge on to see what pressure is when the problems occur?
Yeah, all pressures are in first post. It primes great but once pump stops it drops to zero. Engine turns over several times before starting. Once running pressure is great. Shut off engine and pressure quickly drops to 0 but the engine will fire right back up. Let it sit a couple hours and the same issue repeats.
 

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Yeah, all pressures are in first post. It primes great but once pump stops it drops to zero. Engine turns over several times before starting. Once running pressure is great. Shut off engine and pressure quickly drops to 0 but the engine will fire right back up. Let it sit a couple hours and the same issue repeats.
not a wiring problem when the fuel pressures drop down to zero KOEO ....43psi to zero...

on the truck forums the spectra pumps are highly not recommended ..on a truck IMO much easier to test before setting back everything .. fuel pressure gauge test before completing the job...bed lift ....

I have not replaced the fuel pump on Impala but doing the trunk access hole to get to pump is making this process much less time after its fabricated .. if you are good at working sheet metal and have the tools .
 

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Access hole on a B-Body would be huge,and it isn't that difficult to drop the tank. Not like an F-Body,where the hole makes more sense. Mine hasn't held pressure for years,and runs perfectly fine...
 

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Discussion Starter #6
I cut a hole in a POS sedan I cared nothing about. I actually like this solid wagon so I wont cut a hole in it.

Tank is low enough that dropping it will be fine. If it isn't I will pull the line at filter and power up the pump until it is.
 

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Sounds like a bad Check Valve in the FP itself....just my $.02
 

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Been a long time since mine held pressure. I believe it might have been when installing the adjustable fuel pressure regulator. So,it may contain some sort of check valve/ball itself...
 

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I cut a hole in a POS sedan I cared nothing about. I actually like this solid wagon so I wont cut a hole in it.

Tank is low enough that dropping it will be fine. If it isn't I will pull the line at filter and power up the pump until it is.

this is an old wagon drop tank cut hole and put tank back .. when it continues to act up easy to return the spectra fuel pumps every time they fail.. usually 3-6 months they mess up..before the cover is set back get the fuel pressure testing gauge out ..small cutoff wheel tool works pretty good ...
 

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I did have a recent issue with FPressure bleed off but mine was due to leaking injectors. I doubt that is your issue since this was not a problem for you before and not until you disturbed the tank/fuel pump.
 

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Discussion Starter #11
this is an old wagon drop tank cut hole and put tank back .. when it continues to act up easy to return the spectra fuel pumps every time they fail.. usually 3-6 months they mess up..before the cover is set back get the fuel pressure testing gauge out ..small cutoff wheel tool works pretty good ...
Thanks but I'm still not doing a hack job on my car. Your snarky, high horse comments are assuming that I am putting another Spectra pump back in. Go pretend you know everything on someone else's posts.

I did have a recent issue with FPressure bleed off but mine was due to leaking injectors. I doubt that is your issue since this was not a problem for you before and not until you disturbed the tank/fuel pump.
I'm pretty sure the problem lies in the fuel pump. I was just hoping it would magically be something else :( Sometimes that happens at work but big diesel trucks are a different animal.
 
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