07 Rendezvous Crank no start

[TimeTravel]

Your C305 looks good, dont mess with it any further other than to check for voltage at your next no start/no pressure condition.

Next step is to check for voltage at the fuse, relay, and the power lead wire on the C305 for the fuel pump with the relay jumped.

If you have voltage, and still no fuel pressure, take your fist, or a dead blow hammer, and pound on the bottom of the tank, and you may hear the fuel pump engage. Which means the windings on the fuel pump are getting weak, and the pump needs to be replaced. Had this exact problem last week on my neighbors K1500 Silverado.

The fuel pump has less than a thousand miles on it so far so I'm doubting it's the pump. If it's going to break it has always done it after sitting for the night or after a 12-hour shift at work. I've done Amazon flex a bunch delivering packages and I've never had it not work turning off my car to deliver package.

 

[TollKeeper]

I will just say this... Just because its new, doesnt mean its good.

 

[TimeTravel]

Okay, so again first thing in the morning it doesn't start. I hooked up the fuel pressure gauge and turn the key to the on position and I have no pressure at all. I then checked power at fuel pump fuse while key is in the on position. No power at fuse. I then removed the fuel pump relay and placed a jumper wire between 87 and 30 with the key in the on position and checked power at the fuse again. No power.

Am I testing this correctly?
Should I add another jumper wire from somewhere with ignition power to the fuel pump fuse?

 

[TollKeeper]

If you dont have power at the fuse, you wont have power at the relay..

Sounds like a security issue maybe?

With your key on, look at your dash, what all lights come on, including the box light with multi indicators.

 

[TimeTravel]

Okay, so again first thing in the morning it doesn't start. I hooked up the fuel pressure gauge and turn the key to the on position and I have no pressure at all. I then checked power at fuel pump fuse while key is in the on position. No power at fuse. I then removed the fuel pump relay and placed a jumper wire between 87 and 30 with the key in the on position and checked power at the fuse again. No power.

Am I testing this correctly?
Should I add another jumper wire from somewhere with ignition power to the fuel pump fuse?

Ok I lied. I was measuring the voltage incorrectly. After jumping 87 and 30 on the relay I do have power where the gray and red wires connect to the c305.😅😅

 

[TimeTravel]

I measured resistance from each pin to the chassis.
On the plug side leading to the fuel pump all of the pens read OL

 

[TimeTravel]

I beat the crap out of my fuel tank and it did not kick on unfortunately. I suppose the next step is dropping the tank and making sure I have a good connection to the fuel pump and then replacing the pump again? 😔😔😔😔

Thanks for all the help so far TollKeep. 😂 I know I have not been the best mechanic or instruction follower.

 

[TollKeeper]

Beyond where you are, I am kinda useless. I am good at mechanical work.. I suck at electrical, and would rather pay the dealer! LOL!

Other than to say, I dont know what brand you got for the replacement fuel pump. But I only recommend the Delphi brand, or ACDelco.

The Delphi is cheapest at Autozone, and it comes as a complete assembly.

 

[TimeTravel]

The part number on my mechanics receipt is a30364. A Google search shows "precision fuel pumps" as the brand.

 

[TollKeeper]

O'Reillys Part.. And its within 20 dollars of the OEM Delphi part from AutoZone (AutoZone being cheaper). Hopefully you can warranty it out if it is the problem

EDIT: So the reviews on O'Reillys about that part, are not very good. Mind you its only one review, but its on another 2007 Buick Rendezvous that it failed almost immediately.

https://www.oreillyauto.com/detail/c/precision-fuel-pumps/fuel-delivery/fuel-pumps---tanks/fuel-pump/fuel-pump/83db8e3f0135/precision-fuel-pump-module-assembly/pfp0/a30364

 

[TimeTravel]

Unfortunately the mechanic shop that bought the pump and did the work is about a 5-hour drive from where I am living now... I'll get a Delphi from AutoZone and hope that it lasts more than a few thousand miles 😂. The cheapest one I see on RockAuto is $110 shipped.

 

[TollKeeper]

I wouldnt order anything yet.. Verify the problem first.

I know RA is cheaper, and I even have a discount code for them. But warrantys can be a pain, and returns.

If I am going new, I try to go local just for those 2 reasons.... Unless I am just flipping the car.

 

[TimeTravel]

I've replaced the fuel pump and it works as expected.

 

[TimeTravel]

I wouldnt order anything yet.. Verify the problem first.

I know RA is cheaper, and I even have a discount code for them. But warrantys can be a pain, and returns.

If I am going new, I try to go local just for those 2 reasons.... Unless I am just flipping the car.

I ended up buying the Delphi from AutoZone like you suggested. It was 170 something dollars. Thanks for all your advice.

 

[TimeTravel]

I would also like to mention that I found the old fuel pump float loose in the fuel tank apart from the one that was installed on the old fuel pump. The mechanic obviously did not clean out and inspect the gas tank like he said he did or else he would have seen such a giant piece of debris. Yet another reason I don't trust mechanics.

 

[TollKeeper]

Glad I could help get you back on the road. I dont trust mechanics either, even the dealer.

But alas, I am getting to old to work on cars. 5 blown discs in my back.. Making it really hard to work on cars anymore.

My next car will be brand new, with a LONG warranty so I dont have to worry about it.

Where do you live? I have never seen those C305 plugs look that clean. Its almost like you live in Colorado, or something...

 

[TimeTravel]

I live in San Antonio Texas but I think this car sent most of it's life in Dallas. 🤔 I think the best place for a car is somewhere warm and dry, where they don't salt the roads. Like Arizona. Texas to an extent.

 

[TimeTravel]

😂 After messing about in the engine compartment I found this rubber elbow under the car. Where do y'all think it goes?

 

[TollKeeper]

Looks like the engine vent on the air intake. Or maybe the one for the PCV

 

[TimeTravel]

🥺no fuel pressure again this morning.