In other posts I've mentioned that I believe I need a new fuel pump based on strong gas smell on start up, weak PSI and imperfect idle. I've only had one other car that needed to repressurize the fuel lines between uses, changed the pump and problem gone but I still like to be 100% sure before buying parts and investing my labor in repairs. Replacing parts that don't need to be replaced can be expensive, case in point; recently changed out starter in H2 turned out to be loose cables on the battery from recent repair shop visit for the leak down test.

Currently watching prices for best deal on new pump, lowest $240 delivered.

My question for other H2 drivers, please note year of your H2 in comments. Just turning the ignition key to the on position; how long does pump take to repressurize the fuel lines? Last start up was about 20 hours ago.

 

Link not working. Video of fuel pump starting up to repressurize fuel lines 20 hours after last use. Start to finish 19 seconds.

 

Video is in my photobucket account but I just can't get it to work. Maybe your computers are faster. Here's a pic from my account, it will provide link to account.

 

Crazy enough video link works when I access from my phone but not my personal computer. Here is that link again.

http://i654.photobucket.com/albums/u...psqjfvenqo.mp4

 

I was under the impression that the pump when the key is turned on runs for a given amount of time and is not looking at a set pressure, I could be completely wrong on this one though.

I do have an 08 H2 that I can time to see how long it runs when the key is turned to the run position.

Video link does not work,

Neal

 

2 - 4 seconds if its working properly.

 

Did some web surfing and mechanic Pete on justanswer.com gave this answer to 2003 H2 owner.

Quote: "One common component to fail and cause this problem is the fuel pressure regulator. It can intermittently leak fuel into the vacuum line that connects to it and causes a slight engine flood out which causes extended cranking, in most cases you wont notice any excess smoke when this happens out of the exhaust. This regulator is located on the fuel injector rail on top of the engine and should be on the drivers side of the fuel injector rail. In some cases you can remove the vacuum line and if fuel is found leaking out then it needs to be replaced.

The other possibility is the fuel pump check valve in the fuel pump. It is suppose to maintain or hold the fuel pressure so it doesn't bleed back to the fuel tank. If it is bleeding back fuel pressure then this will cause an extended crank until fuel pressure builds up properly. The fuel pressure would have to be tested to see if it is at fault with a fuel pressure test gauge connected to the test port on the fuel injector rail. Most shops or dealers can test this for you.

Your fuel pressure should be between 55 and 62 psi with the key on and engine off and should hold and not drop off. If it isn't reaching this point of pressure or is dropping off rapidly within a couple minutes then this usually indicates the pump is faulty and needs replaced. The fuel pump is located inside the fuel tank."

I did test my H2 again 4 hours after use and it required 17 seconds to repressurize the lines. When the auto shop did the leak down and fuel line test the pressure was only 49 psi; which is barely enough to run the oe fuel injectors which I believe are rated at 48 psi.

 

Pete responded to a question about a 2003 H2 and you asked about a 2008 H2, these are completely different engines.

My fuel pressure is 44 psi while driving and the truck runs fine, I'll look up the fuel pressure specs for the 08 6.2l engines.

If I remember correctly the 08 has a fuel pump control module which I think is a variable speed pump (PWM). I could be wrong, I'll look it up and see.

I'll run out and do a quick fuel pressure test,

Neal

 

Key in run position and engine off prior to start up the fuel pressure is 60 psi

crank engine and the fuel pressure stays around 59 to 60 psi then drops to 44 psi and holds there while driving.

Neal

 

What brand of fuel pump are you going to buy? The fuel pump is one item that I would only buy the OEM part. I have not had good luck with part store fuel pumps for very long.