2nd fuel pump gone in a month (P0231)

[Mykl]

Is there any aftermarket pump and harness combo that can be used to replace the fire hazard also know as the fuel pump in the VF's? I'm baffled at how this wasn't a major recall. Is there anything you can do to reduce the chances of it happening? Or are we just stuck with the OEM plug and pray?

 

[07GTS]

im not sure if it happens after its been tampered after factory, the plug might be fine when first plugged in but then if its undone and plugged in again or slightly off when plugged in the little tensioned pieces within the female pin dosnt return to put pressure on the newly clipped in male pin, most plugs have a cycle life and alot can be far less then u would think, i can guess holden would only think that over its life time this plug only needs to be unplugged a few times if that...

 

[Martbar]

im not sure if it happens after its been tampered after factory, the plug might be fine when first plugged in but then if its undone and plugged in again or slightly off when plugged in the little tensioned pieces within the female pin dosnt return to put pressure on the newly clipped in male pin, most plugs have a cycle life and alot can be far less then u would think, i can guess holden would only think that over its life time this plug only needs to be unplugged a few times if that...

Mate when the filter in the pump starts to get clogged, could this put the pump under more of a load and as a consequence cook the pins up.

 

[07GTS]

Mate when the filter in the pump starts to get clogged, could this put the pump under more of a load and as a consequence cook the pins up.

no the pins if rated for the load of the pump or little more as fuse is 20amp i think the pins should handle the current just fine, its only when they have a poor connection that they then heat up, resistance has to be dissipated as something and heat is the release, if the pins could handle it and the pump loaded up it would pop the 20amp fuse before anything

 

[Skylarking]

Mate when the filter in the pump starts to get clogged, could this put the pump under more of a load and as a consequence cook the pins up.

Not sure whether the fuel filter within our commodores is on the low pressure side or the high pressure side of the pump itself but it probably doesn’t matter. A blocked filter will cause the pump to work harder (even with a non return line pulsed pump we have in our VF’s).

A pump working harder requires more current to be consumed which results in more heat being generated internally within the pump (heat that fuel flow removes). Running a fuel pump harder than it’s needed is a recipe for shorter pump life and more frequent replacement

But the issue isn’t whether a fuel pump filter is getting blocked by dirty fuel as such should never cause failure of the wiring circuit. The wiring circuit include the wires and the connectors themselves which are all meant to be protect by the fuse.…

So if the design was done correctly and the wire size and pin connector size was chosen appropriately, the circuit would handle the maximum continuous current at the maximum temperatures the vehicle was operated within and it would do so without failure. In these cases, whenever a problem occurs, then the fuse should do it’s job to fully protect the involved circuit from damage.

Put another way, a good design will ensure the fuse is the weak link.

Unfortunately GM/Holden must have skimped just a smidge on their connector design and instead chose something which is just a little marginal in terms of a pins current carrying capacity (especially at higher ambient temperatures). Maybe they did this because it was a few cents cheaper, who knows….

In such cases of skimped design, you’d get exactly what we see with this GM/Holden design. That is a connector pin that heats up because it’s carrying more current that it’s construction allows. As such the connection starts to loose tension which increases resistance which further increases localised heating of the connector and surrounds which ends with a burnt connector…

 

[Mykl]

That's a really good explanation and I had the same thoughts about the fuse being the weakest point. Is there a way to buy a new fuel pump and connector and convert the crappy connector to one that can handle the voltage/amps better?
Correct me if I'm wrong but the problem is on the loom that comes with the car? Buying an aftermarket pump that utalises the stock loom will still pose a threat? My thoughts is it get a pump that (and I'm simplifying my thoughts here) has a bigger connector and then we change the stock loom connector to a bigger heavy duty one that's rated 20amp?

 

[Skylarking]

That's a really good explanation and I had the same thoughts about the fuse being the weakest point. Is there a way to buy a new fuel pump and connector and convert the crappy connector to one that can handle the voltage/amps better?
Correct me if I'm wrong but the problem is on the loom that comes with the car? Buying an aftermarket pump that utalises the stock loom will still pose a threat? My thoughts is it get a pump that (and I'm simplifying my thoughts here) has a bigger connector and then we change the stock loom connector to a bigger heavy duty one that's rated 20amp?

I haven’t looked at the fuel pump wire gauge or the connector size myself but there are resources you can find on the www that specific the current carrying capacity for wires and for connectors used in automotive applications. Using such resources, one could check the design and quantify what current carrying capacity headroom exists above the fuse rating (if any).

It may be that the standard wire size is ok for the intended current carrying capacity. It may even be that the connectors current carrying capacity is also ok. It could just be an issue around the connectors being from a bad batch of poorly manufactured ones that don’t quite achieve what the specs say they should achieve.. Or it could be penny pinching gone a little too far (thinner wires, smaller connectors)… Really, only Holden knows which is the truth but they’d never say… Unless someone who does such automotive circuit design as their day job looks into it and posts the results of their investigation we’ll never really know either…

Whatever the case, if the fuse is 20A then you’d expect a wire‘s capacity and that of the connector should provide some headroom above this amperage so the fuse will always be the sacrificial lamb (so to say)… Unfortunately we just do know why these connectors fail, only Holden does.

Any direct replacement after market pump would be using the same connectors as the standard pump that makes it an easy plug and play swap (though it’s not easy in a VE/VF). After all parts suppliers don’t want to make it harder for people to use their products… In this context, the best you can do is install an access hatch in your VF which makes doing pumps and/or checking connectors a much easier thing (to the point any design/manufacturing deficiencies can be lived with)…

One can always do a big fuel system upgrade and run another non factory styled fuel pump, filter and other bits including new wiring with it which can be beneficial if they want the headroom for future engine upgrades.

@07GTS has a nice build thread which goes into his fuel system design and engine build (if you want to go down that path). He’s also added two nice access hatches in his VE to make serviceability of his upgraded fuel system a little easier . He’s the man to answer questions about fuel system upgrades

 

[Mykl]

Also update from the original post. Mechanic ripped the car apart and checked everything and said it's spotless. All connectors are clean and no sign of fault anywhere. He just thinks the pump crapped itself again. Spoke with Holden and gotta send off the dead pump. If it gets tested and is faulty I'll get my money back. Gonna roll with a Ryco pump for now and see how that goes.