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I install a new gas pump and car running well now, thanks for your help, I learn a lot of think it will be helpful in future.
How did you make sure that fuel pump was fault? Thanks!
p.s. I also have car starting problem and like to make sure if pump needs to be replaced.
Without being sure, I have hesitation - it is costly replacement..
 

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The best way to test a fuel pump for proper operation is to perform a fuel pressure test. Tee-in a temporary fuel pressure gauge between the output of the fuel filter and the fuel rail.
The readings at idle for your car should approximately be as follows:
  • with vacuum hose connected to the fuel pressure regulator: 34 psi
  • with vacuum hose disconnected from the fuel pressure regulator: 43 psi
 

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The best way to test a fuel pump for proper operation is to perform a fuel pressure test. Tee-in a temporary fuel pressure gauge between the output of the fuel filter and the fuel rail.
The readings at idle for your car should approximately be as follows:
  • with vacuum hose connected to the fuel pressure regulator: 34 psi
  • with vacuum hose disconnected from the fuel pressure regulator: 43 psi
Thanks. But problem is, my car wont start. I am not sure that with no-start you can properly perform this test..
I appreciate Any suggestion and share of experience.
 

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Thanks. But problem is, my car wont start. I am not sure that with no-start you can properly perform this test..
I appreciate Any suggestion and share of experience.
p.s. to be clear, in ON position, I hear pump is pumping the fuel. I checked all fuses, relays. Some wirings. I have spark as well. In stalled new spark plug wires. Car do cranks, belt rotates --> so starter seems to be engaged. I am thinking that IACV can be stack? But until removing it [sort of hard removal], I'd like to exclude other possibilities (which are simpler to do in this cold wheather :) )
Also, I already removed injector rail, cleaned injectors and reinstalled.

any ideas appreciated
 

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Sup Mod keeping the peace
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p.s. to be clear, in ON position, I hear pump is pumping the fuel. I checked all fuses, relays. Some wirings. I have spark as well. In stalled new spark plug wires. Car do cranks, belt rotates --> so starter seems to be engaged. I am thinking that IACV can be stack? But until removing it [sort of hard removal], I'd like to exclude other possibilities (which are simpler to do in this cold wheather :) )
Also, I already removed injector rail, cleaned injectors and reinstalled.

any ideas appreciated
The fuel injectors may not be getting pulsed by the ECU; you can test each injector with a "NOID light probe tester" to see if it's pulsing. The probe kit can be puchased at most auto parts stores or online at Amazon.com. Each injector has two wires; one is the signal wire and the other is a constant 12volts; test each injector for 12v with a multimeter.
Thanks. But problem is, my car wont start. I am not sure that with no-start you can properly perform this test..
I appreciate Any suggestion and share of experience.
You CAN test the fuel pump with the fuel pressure gauge while the engine is not running. Tee-in a temporary fuel pressure gauge between the output of the fuel filter and the fuel rail. Turn the ignition key to the RUN position but DO NOT TRY TO START THE ENGINE. The fuel pressure reading should be around 43 psi which would be a static reading.
 

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rogoman, thanks for prompt reply.
I forgot to write, that I done tests with injectors. Before rail total re-installation, connected all 4 injectors to the power feed. During crank they all spray fuel (in 4 plastic bottles attached to injectors' 'noses'. So, I avoided to pour fuel around..).
Also I measured their resistance and reading was R=10 oms. So, injectors look fine.
I'll do pressure check between fuel pump and rail at ON position. Will post result here.
p.s. Can fuel pressure regulator (FPR) be tested too at ON position? Can fault FPR be the reason for the no start?
 

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With the engine shut off, if the fuel pressure gauge shows a good static pressure, that shows that the FPR is maintaining the pressure, meaning it's OK up to that point; further testing of the FPR should be performed once you're able to start the engine. If the fuel pressure is very low or zero, then the FPR or the fuel pump is bad.
 

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Good day everybody,

Today I done some fuel pressure measurements. Installed pressure gauge between fuel filter and fuel rail [just after the fuel pressure regulator (FPR)]. With key ON position, in first 5 seconds there was 40 psi [bit more than that]. But, after it dropped below 20 psi [even keeping ON position]. When I was cranking, right after that 5 seconds, then 40 psi was maintained (but no start).
But, without crank, pressure drops fast around 20 psi. Then, right after FPR I shut the return line hose [by ‘clamp’ type devise], and at ON position 50 psi pressure checked. And it maintained for a while even after going to the key OFF position.
With this steady pressure regime, I did crank but did not manage to start.
I replaced FPR (had another one), but got exactly same results.
Definitely, there is pressure leak somewhere after FPR. However, since with return hose shut the pressure maintained and there was no start, I am not certain to blame only the fuel pump. There should be other problem too.
Now, I am thinking to try this way of starting:
If car will start, then probably culprit is the fuel pump? But if still no start, then there should be other problem(s) too.

I also saw this video:
According to that logic and things I done, my injectors have no leak.
I also exclude FPR, because both can not be fault.
Any comments on these?

P.S. Since we had good sunny day today, I took the chance and cleaned throttle body. Also mass airflow sensor [although the latter is not major for car starting]. The did not help so far.
 
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