Fuel Pump Odyssey -- Why are there still starting issues? 2010 Pontiac G6

2010 Pontiac G6
4 cylinder
143,000 miles approx
Purchased 2011, was a lease and I’m the only owner since then.
2021 Fuel Pump replacement: 19208646 B-(S) Module Kit

TL;DR Replaced the fuel pump twice in 5 years. Recent replacement is March 2021 @ Colorado GM dealership. Car wouldn’t turn over a week ago (April 2021), & Montana GM mechanic replaced the battery & negative battery cable. Car started at the dealership. I picked the car up & after driving 90+ miles car wouldn’t turn over again. Same sounds, same problem. What could be the issue?

The fuel pump was replaced in 2015/2016. No fuel pump or starting issues since then. Car wouldn’t turn over in March 2021. Got fuel pump replaced by Colorado GM Dealer w/ 2 year warrantee. About 1 month later the car wouldn’t start again. In a different state, now at a Montana GM Dealer. Was told by a GM Mechanic in NY state that the issue might be that the CO Dealer improperly installed the fuel pump & the fuel pump connector needs to be checked.

The MT Dealer didn’t agree. Said it was an old battery and a corroded negative battery cable that was the issue. MT Dealer replaced both, car started, and I guess they could drive it around the dealership. After asking them to check the fuel pump connector a 2nd time the MT Dealer tech put the car up on the lift, “wiggled the fuel pump connector” cable and the car didn’t turn off. They determined it wasn’t the fuel pump connector.

I picked the car up 4/23. Drove the car 90+ miles on 4/24, car wouldn’t start with the same problem. Got it towed back to the dealership and they’re not available until tomorrow 4/26.

Is it possible that the fuel pump connector ISN’T the issue? I watched some videos of fuel pump installation and the electrical connection is at the top of the fuel tank, so it’s possible that connection has an issue or the connector part is crappy, but I’m in the Knucklehead category when it comes to cars.

I can provide more info on request.

First, clarify “wouldn’t turn over.” Is it

  1. the starter motor does not make its normal sound and make the crankshaft rotate, pistons go up and down, etc.?

  2. the engine does turn over as usual, but does not start and run?

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I’m not sure what the difference is between those 2 options, this is all pretty foreign to me.

The best way I can describe it is a declining response: the first time it revs, turns over, starts, and dies. Then the turn over gets progressively worse to the point where it just revs.

Does that address your questions?

It almost starts and runs at first turn of the key - but subsequent turns of the key the engine turns over but gives no hint of starting and running. That sounds like there was residual fuel at the engine, but it is not being replenished. And that sounds like a fuel pump that is not running.

Could be bad pump, bad pump relay, bad wiring/connector, bad ignition switch, etc.

Copy that, thank you! So the only way they figure that out is by taking the fuel tank out and checking everything?

Do you know what could cause a fuel pump to fail in one month?

Don’t jump the gun. There may be no fuel pump problem. From your description, we don’t even know if the starter is cranking the engine.

The only way I resolved fuel pump problems in my Riviera was to junk the car. Several right out of the box were faulty. Toward the end they would fail every year, almost to the date. Yes the connector was a problem too once and the shop roughed it up pretty good and that seemed to work. But when replacing a fuel pump, the harness, and relay should be replaced along with the pump. Excess current can cause a problem. I will not fuss with GM fuel pumps anymore and junked the Olds when the pump failed.

Hmmm… that was the same situation that I had with my POS Volvo.
And, like you, I finally junked it.

I’m going to the Montana dealership tomorrow to discuss the unresolved issue and the mis-diagnosed repairs. Hopefully things go in a positive direction.

I’m hoping to get at least a refund on the mis-diagnosed problem and hoping the actual repair falls under the fuel pump warranty, which was the March 2021 repair.

If it can get me out of Montana and Colorado in the next week I’ll be happy. The next step is to sell it for what I can.

I never purchased a fuel pump for any of my Chrysler products. I did have to replace one on a slant six duster but I had a couple no my parts sheild from cars I had junked because of rust.

A daughter’s boyfriend got stuck at our house with an AMC Gremlin That would start but stumble and die with gas pouring out under the air cleaner. I got out my vacuum gauge and fuel pump tester and hooked it up and when he cranked it it pegged my gauge which only went to 6 pounds, I looked in Motors repair manual and his cal only called for 4 1/2. He said he had just bought the fuel pump and showed me the receipt. We went and got another fuel pump, came home and same result Went back to the parts store and the counter guy and I were yelling at each other.

He was saying he was not going to give me another fuel pump and I was saying we did not want another of his fuel pumps unless they were going to start paying me for putting them in.

       He gave the kid back his money and I asked the kid why had he changed the furl pump and he said one of his friends had told him to because it was old. We drove to his house got the old pump and put it in and the car ran fine.  I kept the receipt and the next time I ent to NAPA I asked the counterman if this was the right pump for a Gremlin. e said no, that id for a Chevy with 13 pounds pressure.  They looked like the same pump but I always wonder if it was for a57 Fuel injected Chevy 283.

Well good luck. The only thing I’ll add like mentioned already is the terminology. When you turn the key, you hear the starter motor turning the engine over but the engine does not start. That is called cranking or turning over. If the engine starts that is called firing. Now if you turn the key and nothing happens, no sound, that is different and could be bad battery, starter motor, etc. You can check if the battery is bad by turning the lights on to see if they light up. Just to clarify is all when talking to mechanics and other people. One of the factory service manuals I have has at least two pages of definitions of sounds and conditions to help with customer complaints. Terms like chuggle, miss, etc.

Engine wouldn’t turn over, shop replaced the battery and now you have the same problem, the engine “revs”.

This is a technicians nightmare, vehicle starts and drives after replacing a dead battery and misleading information from the customer. Sometimes the wrecker drivers leave the ignition on draining the battery so a no-crank complaint and a dead battery can misguide a technician.

There is a possibility that there is a poor connection at the fuel pump but why would anyone investigate this for free for a no-crank complaint?

There is hope that they will refund your money and return the dead battery to you.

Thanks!

I’ve had a dead battery before where the car wouldn’t give any response to turning the key. At the time we thought it was the starter, but it turned out to be a dead battery (this was back in high school).

With this particular Pontiac issue it didn’t have a dead battery (once in March 2021, twice in April 2021). What I told the service rep – car wouldn’t turn over – is what they experienced at the shop. The battery had some corrosion on the negative side and the negative battery cable was corroded, so they replaced both thinking that was the problem.

How is the information I gave misleading? The shop experienced the same problem I did – heard the same noises.

The battery was never dead. It had some corrosion on the battery, and the negative battery cable had corrosion so they replaced both hoping this would fix the issue. It seems that you were confused when I wrote “didn’t start again” – I meant it didn’t turn over again, not that it didn’t crank. You could argue that was my mistake for this post, but the “again” indicates that I’m experiencing the same issue, where earlier I wrote it wouldn’t “turn over.”

The dealership should have investigated the fuel pump because there wasn’t “a no-crank complaint.”

After having a number of Uber rides around town, I’ve found out that this particular dealership has a bad reputation. In fact, one of my Uber drivers had an issue where this dealership’s shop made her car worse and wouldn’t take responsibility for their mistake – financially or, at the very least, verbally.

This is where your terminology is confusing:

“Turn over” and “crank” mean the same thing: that the starter motor is spinning the crankshaft as it should.

If the engine is turning over, it is cranking. If it does not start, then we say “It cranks OK but does not start (or fire, or fire up.)”

A bad battery or battery connection is a common cause of a no-crank. It might have enough juice for some lights, and to run a fuel pump, but not enough to make that starter motor spin.

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Ahhh, understood. Thank you for the clarification.