I didn't see one either I wanted to see it I would have thought once you turn the key off naturally the pressure will drop unless there is a one way valve.
According to factory shop manual for a 2004 GMC Envoy/ Chevrolet Trailblazer, Buick Rainer, the pressure is checked with key on and engine off and should be 50-57psi. It states to activate fuel pump, turn key on without starting engine, turn on key at least 3 times to activate pump. The third time activating pump, check pressure. The pump will activate, but with engine not running, it will stop. When the pump stops, it should stabilize, hold pressure and pressure should not drop more than 5psi This is procedure for 2004 and other years could be different. My 2004 Envoy did have port by the fuel filter near tank and had a black twist on cap covering it. There is a green cap under the hood, but that is for fuel vapor/evap check.
Had the same issue with my 02 4 runner. Picked up a bad load of fuel. Fortunately my fuel filter is on the frame rail. Replaced and issue solved. Also...I cut the old filter and it was clogged ... That's my Huckleberry!!
Hi, I had this problem, but it Was not the fuel pump check valve, in my car the problem was the oring that conect the fuel pump with the cover, it crack and start to leak the pressure, change the oring and it work fine again, but thanks to this video I found the problem.
Nathan, the fuel pump is electronic not mechanical. You don't have to crank it. Turn the key on twice wait 5 seconds for the pressure to build and it should start right away. If not.....fuel pump.
Enjoy your videos, a possible quick fix you might want to try and is free is to take a deadblow hammer to the bottom of your tank right where the fuel pump pickup is and give it a few “love taps” nothing too aggressive but just enough to jiggle the fuel pump a bit so that whatever is stuck in the check valve assembly might possibly shake loose. A healthy dose of sea foam in the tank with low level of gas can’t hurt either those 2 things may also help and prevent dropping the tank. The reason I say that is by the pressure gauge it looks like the pump builds pressure very well but the pressure just reversed back into the tank and not holding press to the rail. Best of luck !
I had an 04 Rainier for 10 yrs it took forever to start after I put gas in it so when I went to the gas station I would just leave it running now a year later I bought a 03 Trailblazer
I have a 2000 blazer just sputtered & stopped running while I was driving. It has spark & fuel does come out of the port on the rail. I have to get a gauge to check pressure. My question how to tell if it is the fuel pump or the fuel regulator? Thank you in advance for your help. Joe Z
It's making pressure so how could it be the fuel pump and the regulator is what you pulled the fuel lines off of for your gauge it's not in the tank and there's a test port that comes off the fuel filter under the driver's door on the frame
Thanks for the valuable information. I have a problem that the car was working, and after I pressed the gasoline, the car stopped and no longer works. I checked everything, but I did not find a solution to the problem.
My 04 Trailblazer has a fuel pressure of 49 psi with key ON and about 52 psi on idle i read that fuel pressure on these trucks should be between 50-57 psi should be worried for the 1 psi below spec?
@@FixingWithPassion If there is a valve under the Trailblazer, it is plastic lines/valve has a metal schrader valve inside it. It has a plastic cap covering valve, shouldn't be rusted.
My 2nd Video shows what went bad. There's a link at the end of the video.
No there isn’t.
I didn't see one either
I wanted to see it
I would have thought once you turn the key off naturally the pressure will drop unless there is a one way valve.
According to factory shop manual for a 2004 GMC Envoy/ Chevrolet Trailblazer, Buick Rainer, the pressure is checked with key on and engine off and should be 50-57psi. It states to activate fuel pump, turn key on without starting engine, turn on key at least 3 times to activate pump. The third time activating pump, check pressure. The pump will activate, but with engine not running, it will stop. When the pump stops, it should stabilize, hold pressure and pressure should not drop more than 5psi This is procedure for 2004 and other years could be different. My 2004 Envoy did have port by the fuel filter near tank and had a black twist on cap covering it. There is a green cap under the hood, but that is for fuel vapor/evap check.
Bad check valve in the fuel pump assembly. Nice video
Had the same issue with my 02 4 runner. Picked up a bad load of fuel. Fortunately my fuel filter is on the frame rail.
Replaced and issue solved.
Also...I cut the old filter and it was clogged ...
That's my Huckleberry!!
04 Buick rainier is the same thing but has a port by the fuel filter for hooking up the gauge
Nice!!
I lose acceleration pressure when driving sometimes amd then it'll pick up again. I think it's the fuel filter
My '04 has a fitting at the fuel filter but where they put that filter some engineer needs a wedgie.
Hi, I had this problem, but it Was not the fuel pump check valve, in my car the problem was the oring that conect the fuel pump with the cover, it crack and start to leak the pressure, change the oring and it work fine again, but thanks to this video I found the problem.
Good deal!
Nathan, the fuel pump is electronic not mechanical. You don't have to crank it. Turn the key on twice wait 5 seconds for the pressure to build and it should start right away. If not.....fuel pump.
Such a nice truck
Thank you guy i have to put one in tomorrow and i will be checking my fuel pump also. Thanks
Great!~
Enjoy your videos, a possible quick fix you might want to try and is free is to take a deadblow hammer to the bottom of your tank right where the fuel pump pickup is and give it a few “love taps” nothing too aggressive but just enough to jiggle the fuel pump a bit so that whatever is stuck in the check valve assembly might possibly shake loose. A healthy dose of sea foam in the tank with low level of gas can’t hurt either those 2 things may also help and prevent dropping the tank.
The reason I say that is by the pressure gauge it looks like the pump builds pressure very well but the pressure just reversed back into the tank and not holding press to the rail.
Best of luck !
Good Idea!~
I had an 04 Rainier for 10 yrs it took forever to start after I put gas in it so when I went to the gas station I would just leave it running now a year later I bought a 03 Trailblazer
Hey I have a 2008 trailblazer and I have to put gas in my Throttlebody for it to start and it shut off afterwards
The fuel pressure test port is by the filter on 2002-2004
Cool!!
But does anyone know where to get an adapter for that size port? Loaned Pressure tester from auto parts store would not fit it.
@@waynesallee-com on the 2002-2004?
@@dealerauctionnightmare4689 Yes. My trailblazer is 2002.
@@waynesallee-com your port is under the car by the fuel filter.
Great info!
Nice diagnostic. We have an 07 Envoy, so this is good info for me.
I see your'e a hoarder like I used to be.... Throw it out! Listen to the wife... :)
There's a green cap under the pliars to hook up pressure tester
That's evap.
The check valve in the fuel pump is bad allowing the fuel to run back into the tank.
True!!
I have a 2000 blazer just sputtered & stopped running while I was driving. It has spark & fuel does come out of the port on the rail. I have to get a gauge to check pressure. My question how to tell if it is the fuel pump or the fuel regulator?
Thank you in advance for your help.
Joe Z
Nice!
@@FixingWithPassion My question how to tell if it is the fuel pump or the fuel regulator?
Thank you in advance for your help.
Joe Z
It's making pressure so how could it be the fuel pump and the regulator is what you pulled the fuel lines off of for your gauge it's not in the tank and there's a test port that comes off the fuel filter under the driver's door on the frame
Thanks for the valuable information. I have a problem that the car was working, and after I pressed the gasoline, the car stopped and no longer works. I checked everything, but I did not find a solution to the problem.
Question what can cause a lean code if you don’t have any vacuum leak
Bad o2 sensor up-stream
Bad fuel pump can cause lean codes buddy little people no about this issues am fighting to long to fix that codes in my mechanic life 🤟
pretty good men👌👌
My 04 Trailblazer has a fuel pressure of 49 psi with key ON and about 52 psi on idle i read that fuel pressure on these trucks should be between 50-57 psi should be worried for the 1 psi below spec?
No only if it slowly bleeds off.
@@FixingWithPassion Thanks for responding...I did a leak down test for about 10 minutes and there were no drops, I guess I'm good then?
why wouldn't you just use the schreider valve test port at the fuel filter, screw in the pressure gauge and go easy peasy.
Rusted tight place
@@FixingWithPassion If there is a valve under the Trailblazer, it is plastic lines/valve has a metal schrader valve inside it. It has a plastic cap covering valve, shouldn't be rusted.
I haven't finished watching the video yet but I say low fuel pressure.
What pressure should it be when primed
45 ish.
@@FixingWithPassion thank you very much. I'm getting 10 prime, 60 running, so I have a problem
And the injection are not spraying when I crank over the truck
Fuel pressure testing port by fuel filter
That's the problem that when there's starting problems, you all start messing with the fuel system, which is not the problem
There is a tap on the fuel rail so you don't have to make a rig like that,
It is at the fuel filter out going fuel line. Yep under the car how convenient.
Check your throttle body, may need cleaning too much gum and dirt get stuck