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Crank No Start. Spark and Fuel Pump are Good

6018 Views 95 Replies 18 Participants Last post by  arnoldsmind
I am working on a 1996 Impala SS with 180K Miles. I have a crank no start issue. Car runs with starter fluid, but nothing after that.

I uploaded a video on YouTube to give a 1st hand look

So far: New Battery, New Fuel Pump Relay, Fuel Pump Working, spark confirm, fuel injector fuse in tact, fuel being delivered to engine, no fuel pressure at Schrader valve..
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If I were to guess and your info is ACCURATE,

Blocked fuel filter
Leak between fuel pump and the sender- holder so fuel isnt building any pressure .
Regulator is jammed open so the fuel is being returned from the rails before any pressure is built up.

Get a pressure gauge on the rail.

Verify the pressure or lack of it

I would begin by removing the return off the regulator blocking it and momentarily activating the pump.
If it pins the pressure guage then the regulator is the culprit.
If no pressure and you are positive ( back to your info) the pump is running, you either have the big leak inside the tank or the filter is plugged solid.
The Fuel is getting to the engine. I captured it in the second half of the video I recorded and added a link to.
No fuel pressure at schrader valve either means that the fuel filter is completely blocked or the fuel pump assembly is not doing what you expect.

You mention Fuel Pump Working - How do you know this?

Replace $12 filter if you're unsure, but probably not the case

Fuel pump may not be pumping
Tank may be out/low on gas
Tube coming out of fuel pump may be broken/split/disconnected
Fuel pump is operational and the line is in tact. I disconnected the inlet line and recorded fuel coming out at the fuel rail.
My apologies - I didn't watch the video initially.

I'd start with what 95wagon mentioned and look at the fuel pressure regulator.

With a fuel pressure gauge on the shrader valve, Pinch/block the return line and see if it builds fuel pressure.
I took the battery to Autozone to get charged. I will work on the Regulator in the AM.
please always use a fuel pressure gauge. Pumping gas into the engine compartment like that is extremely risky.

Can you post a video with your phone directly below the gas tank while you turn the ignition on? I want to hear how the fuel pump sounds.

I have learned the hard way on these cars and others that just because you can hear a fuel pump running doesn’t mean it’s producing usable pressure.
I added the video you requested to my iG story.

you do the fuel pressure gauge ... the correct pressure is 45-47 psi to turn the key on no engine cranking ..
the fuel pressure is dropping around 37psi no engine running ....
also if the fuel pressure is using the hose in the container your not gone to do the pressure ....
my 96 Impala changed the fuel pump ,,,, inspected it of the electrical contacts cleaned it .. the fuel pump was the positive contact and the harness connection then I changed the connector .. the fuel pump motor was the positive brush and the brush was worn out ....
Are you saying that the regulator was moved to the pump? Should the fuel be coming out as more of a spray?
I'm headed to Harbor Freight to get a Fuel Pressure gauge. If there is no pressure what is the next step? If it was holding pressure shouldnt fuel come out of the schrader valve?
If you haven't get a gauge on it.

Fuel running out of the hose at no pressure doesn't nessasarily mean there isnt a leak at the pump ,
It could freely run out the line at the front with no restriction but stop flowing , pissing away in the tank, as soon as you ask the system to build pressure.

Or the regulator is dumping the fuel back to the tank not allowing the pressure to rise in the rails
With the return hose disconnected there was no fuel coming out to go back to the tank. It seems like the fuel is getting stuck at the injectors. Wouldnt the fuel injectors send enough gas to an engine and start it even if it rev'd low?
Purchasing is not expensive, but for as many times as you'll use one most parts retailers will 'loan' (with deposit) a complete setup. I grabbed one from AutoZone last month to check the Sister In Law's SUV. Their kit turned out brand new and with every imaginable adapter and fitting. And yes, it was the pump and all I had to do was lift the back seat to expose the hatch.
What am I looking for that would differentiate between the problem being the Fuel Pump vs Something else. My Vice Grip Garage school of automotive technology license taught me that if the Schrader is dry there is no pressure and the Fuel Pump is out. But that’s not the case here. A leak in the tank doesn’tThere's fuel delivery. The leak would have to be in the fuel line, and that would show as a fuel on the floor. Full transparency, I’m dreading having to drop the tank, It’s half full. I want to explore all options before changing out a working fuel pump and being back at square 1.
Please post the outcome of your case. I am having similar issues. Thank you!
Will do. Fuel pressure gauge arrives today
Or you could just drop the tank already... The pressure gauge is not going to tell you anything you don't already know.
I will. I will work on finding that fuel pump trigger wire. I will go through all steps given by forum member. I will take all the advice I asked for. I will get over my PTSD from dropping a full tank. Ended up snapping a line on my last install.


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I was dropping the gas tank behind the bumper , two bolt straps I was using the rear diff of the jack lifted it up and then higher then sucked out the gasoline ...then drop it the tank , and take the hoses off....
I was the GM did the hoses of the rubber of the chassis metal tubes ..that picture is a mess

....the fuel pump connector is the license plate .
That pic is a fix on an 05 Trailblazer.
Last time for me ,

If the line INSIDE the tank is loose or has a split, fuel will still run out the front when there is no resistance ( as in an open line )

Ask it to build system pressure and the fuel chooses the easy route and pushes through the split and doesn't flow forward anymore.

A really lame pump can exhibit similar symptoms.

Can flow fuel at zero pressure , will flow nothing when asked to build pressure.

Rarely bad grounds can show similar simptoms but I doubt it here.

As in bad ground , the current finds a new route to ground like, through a lamp filiment.

As it to make pressure , the draw goes up and the " new path" will not carry the load and the pump stops.

Good luck with your search.
No pressure confirmed with the gauge. Here is a pic of the gas.


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I'm closer to swapping in a carb and intake like this guy.

Here is a video of the inlet hose running. I blew through the same hose and was able to blow through, I just looked like a trumpet player.

The carb won’t like 0 fuel pressure either.
That’s clearly enough fuel to run a
The carb won’t like 0 fuel pressure either.
This looks like more than 0 fuel pressure to me. I added the video to my story.

Sorry, I’m not on instagram. Just report the numbers from the fuel pressure gauge.
Still 0. Changed the fuel filter, here is what I'm getting now.

You've confirmed that the reason the engine doesn't run is that fuel is not getting through the injectors into the engine - Good

This means that either the injectors are not being told to open by the ECU or that there isn't enough fuel pressure to open the injectors when the ECU commands them open.
The injectors need a minimum fuel pressure to open - if there isn't enough pressure, they won't open just a little and the engine runs at low power when the ECU commands them open - they won't open at all. This is an "AND" scenario - you need the fuel injector commanded open by the ECU - AND - more than 45psi fuel pressure for the injector to open and deliver fuel to the engine.

Injector commanded by the ECU and less than 45 psi fuel pressure = no fuel in the engine
More than 45 psi fuel pressure, but no command from the ECU = no fuel in the engine
Injector commanded by the ECU and 45 psi of fuel pressure = fuel in the engine and it'll run

You mentioned that you have a fuel pressure gauge - what does it read with the key on/engine off? You can't tell anything by looking at the port, you need a pressure gauge to tell what the fuel pressure is.
The gauge doesn't move at all. Under any circumstances.
Are you sure the gauge is working? Try the gauge on another engine.
I will check it on my truck.
Drop the tank. Upgrade the fuel pump (walbro 255lph) and add adjustable regulator (accel or aeromotive). Set to 45psi. My car just ran like schitt when my OEM injectors went bad. If you are replacing injectors too,, don’t go cheap and replace them all (no hecho in China - unless Delco (ha!)

also, though it doesn’t sound like it in the video, but you may want review intake side for leaks or loose connectors. Loose MAF and MAP will also cause car to turn on and right back off.
I will get after it on Friday.
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