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Replaced fuel pump car now won't start

I have a 2005 buick lacross 3.8 liter v6.
Starting from beginning.
I accidentally put water in my gas tank. In the process of removing water/gas from my fuel tank, I was told my fuel pump went bad. Went and got another fuel pump and completely drained all water and gas from the tank and wiped it clean.
Replaced the fuel pump.
Went to start the car and it will not start.
I replaced fuse for the fuel pump itself and still not having any luck. I need any suggestions please and would greatly appreciate it. Thanks guys.

the very first thing . . . you need to make sure everything is properly hooked up. There are quite a few electrical connections and fuel lines involved when replacing a fuel pump

then you verify proper power and ground at the fuel pump when cranking the engine

Turn the ignition switch on for two seconds so the dash lights turn on, and then turn the ignition switch off.

Repeat this a half dozen times and then try starting the engine.


I agree with Tester. Try priming the fuel system via his method.

Are you certain the replacement fuel pump is powered up and running & pumping the gasoline from the tank to the fuel rail? It’s usually possible to hear the pump running. Sometimes it helps if you hold the tip of a screwdriver against the fuel tank near the pump and listen with your ear to the end of the handle. My guess either the pump isn’t powered up for some reason, or it’s faulty out of the box.

There’s one other consideration is cases like this. Sometimes fuel system testing floods the cylinders. The engine simply won’t start when the cylinders are flooded, even if everything else is ok. Remove a spark plug. If you smell a strong gasoline odor from the cylinder and the electrode is wet w/fuel, that’s probably the problem.

I would 't have guessed water in the gasoline would have damaged the original pump, unless it was inside the pump for quite some time, weeks or months.

My guess is the original fuel pump was fine, what ever stopped it from working is still your problem,
I’d check the fuel pump relay.


For curious minds , how did you do that ?


Same way people accidentally put diesel in gas tank would’t never tell.

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I would also concur with Mr @Tester… During the fuel pump replacement process you drained a large portion of the fuel system. Once you were finished and attempted to start the engine…the fuel pump had only run about two seconds per key on and off cycle… The fuel pump will run constant after the computer reads a tach signal…but not until then.

Telling you to “cycle” the key a bunch of times…basically strings together those 2 second fuel pump prime events until basically it equates to running the pump for many seconds.

Or… you could be clever and remove your fuel pump relay and bridge terminals 30 and 87 with a wire and run the pump as long as you like until pressure is in the rail and you are able to start the engine.

To each his own…

Thank you for your time and concern. I truly do appreciate that. Okay so. I know that the fuel pump is working and in getting fuel to the fuel rail. I checked the spark plugs and when testing fire for one noticed some droplets of water that came out of where the spark plug was. So I pulled all 6 spark plugs and turned key over for just maybe 10 seconds or so and leaving out overnight just to let air dry. It wasn’t much water at all and only really noticed any out of cylinder 1. I was wondering if you had any other suggestions at all. I would appreciate it very much.

Keep in mind… if you have water in your tank… it is resting peacefully on the very bottom of your tank and all the fuel is floating on top of it. That fuel is also now phase separated also so the ethanol has left the gasoline and joined the water in the bottom of the tank. Ethanol loves to hang out with water. None of this is good to be honest… If its cold enough…that water will now be ice or trying to be. Fuel pumps hate this. So its important to get that water out.

The fuel that your pump has now pushed up to the rail may be so diluted or messed up at this point that it wont fire normally. So you may need to drain the tank and start with fresh fuel…depends how bad this situation is… which is directly proportional to how much water you put into your tank.

Only you know how much water and fibbing wont help so…

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He actually drained/dried the tank, told so in the very fist message:

I think at this point, the water may still be in the fuel lines.

I would disconnect the fuel hose form the rail, then put it into the plastic bottle and while firmly holding it this way, asked a helper to fiddle the ignition on and off few times until the fuel line is completely purged of water, thn reconnected to the rail and likely that would be all it needs to start.

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Oops… shows you how much I read sometimes… My bad.

I also concur with blowing out the lines… run the fuel pump by bridging the FPR and let it run into a jar… then once confirmed good fuel is present… Try starting again. The fuel hoses and rail hold a good amount of fuel.

so… you are a writer, not a reader :slight_smile:

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I’m a moron actually

the stream will be quite strong, so a jar may allow it to spill around

I think a plastic bottle from Coke with a narrow top will do a better job capturing spills

Please describe that process . . .

Did you remove the fuel tank and completely drain it of water . . . ?

Or did you use some other method, and you think you drained all the water . . . ?

And as far as I know, you still haven’t told us how you managed to get water in the tank, and the volume of water that wound up in the tank

My WAG you have water in the system, some starting fluid could give enough kicks to let the water run through and get to good gas.

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There was a one gallon gas can in one of step dads cars. It was half empty. Step dad had a car overheating and put water in can for his car. I didn’t know. And the process I mentioned was I attempted to siphon the gas out but couldn’t get all of it. So I removed the whole fuel tank. And yes completely emptied all gas and water. Put in new fuel pump and new gas.

Did you purge the fuel/water from the fuel line at the fuel rail?