94 camaro LT1.

Hi guys, hopefully someone has an answer. Weeks ago I through a code 32, so I replaced my egr value. Either right or shortly after, my car started to take a while to start. It cranks, just sits and cranks for quite a while until it starts.

Replaced:
Fuel pump; stock 200 dollar autozone replacement, have access door
Fuel pressure regulator
Checked all injectors for leaks, and replaced all o rings. Only o ring I couldn't replace is the one at the end of the fpr but it didn't have any cracks.

Rented and tested fuel pressure. All pressures seem fine, except when I turn off key. In a matter of seconds I lose it all, it goes to zero. Turn key to prime pump, pressure shoots up, them after the pump turns off (two-three seconds) it drops again in seconds to zero. Is the pump a lemon? Where can a find a good check valve in line for my car?
Also, I replaced the pump a few months ago thinking it was bad because it wouldn't turn on, come to find the three wires melted together, so I fixed them with speaker wire and black tape. It all looks fine still

Any ideas? Car runs perfect other than that issue.

 

I've seen this after a new pump replacement where the clamp on tube on the pump wasn't tightened enough and pressure was leaking back.

 

Could you explain what one your speaking of? The one that goes to the pump, located inside the tank having the clamp?

 

The fuel pump pulsator on top of the pump. It is the hose that connects the fuel pump and sending unit. The price of 200 makes me think it is a whole sending unit/pump combo. It could be one of 4 things. 1Fuel pump/sending unit,2.pulsator, 3.fuel leak, 4. fuel pressure regulator. If i had to guess it is the autozone pump. I say if it moves or electricity runs through it. Don't buy it from autozone.

 

Its the whole bucket and pump. Doesn't come with anything outside the tank. I bought some Uv dye for fuel, will try that as soon as the tank gets lower. Any obvious places to look? Any way to test leaks in the tank around pump? Like, run it out me the tank or something?

 

Ussj,

I think I might be having the same problem. When your car finally "catches," does it do so quickly and reach normal idle, or does it hesitate for a few seconds while it "catches" before reaching normal idle?

 

There's a check valve in the factory pump that holds pressure. If the pump you bought does not have the check valve or if it is defective you will immediately lose pressure once the pump goes off. This was an issue brought up about the walbro high performance replacements.

Byrons1502 is stating something I have heard over and over again. AZ has such a terrible reputation building regarding their electrical parts....

 

Sometimes it starts them the idle shoots up, then back down, and sometimes when it finally starts its just a regular start off. Always a long crank time though. I'll probably be replacing the pump, again, too bad if autozone doesn't like me replacing them, if they bad, that's there fault.

 

Could one see this valve and try to determan if its bad or not without breakidg the bucket?

 

I wish I could answer that for you. I have not worked on the pump you are dealing with. I can say this though; I cut the metal casing from the failed pump out of a my Pontiac Grand Prix just to see how it worked. It was the strangest mechanism I have ever disassembled. The motor, armature, brushes ET AL are immersed in gasoline. I can't believe these things do not have at least one spark that turns each car on the road into an explosive device when the tank goes empty and some free oxygen is introduced to the gasoline vapor. Anyway that little DC motor drives a series of elliptical plates which all have non concentric slots that somewhat align upon intervals. The plates are all driven by a cam lobe which gives them a controlled wobble. To conclude this long story, I was so baffled by the construction that I had to assume the check valving was accomplished when everything stopped. And I could be entirely wrong about this.

 

Hahahaha!!!! And there you have it ladies and Gentleman. The governments secret method of population control. Human BBQs...

But yeah, I am still trying to figure out my problem. In general, I never buy from AutoZone for anything except name brand parts like Delco and MSD. Otherwise I'll only use them for oil, filters, electrical, etc etc.