5 replies to this topic

[7builder]

My SPi keeps blowing fuel pump fuses so today I have taken the car apart and traced the wiring as suggested in several posts and can find nothing obviously wrong. Could the pump be the fault here? The problem is that once the fuse is replaced it runs fine for a while then blows another fuse at random intervals. Sometimes I get through 2 or 3 fuses a day and other times it is fine for a couple of days.

This is driving me nutty now but don't want to spend out on an expensive pump if it isn't that at fault.

[Fast Ivan]

one check would be to remove the power feed to the pump and start her up, if the fuse doesn't blow then it points to the pump, if it does blow then the problem is further up the wiring, possibly relay related, tricky with it being intermittent intervals though.

It could possibly be a partially blocked fuel filter  

[7builder]

Thanks Ivan I will give that a try.

 

Thanks for responding. 

[Homersimpson]

As another test you could disconnect the pump wiring (I assume its just a power connection?) and use this to switch a temporary relay.  You could then wire a feed directly from the battery via a fuse of the same rating as the car normally has, through the relay to the pump. 

 

If the fuse still blows then its the pump, if not then its something else on the circuit (does the fuel pump circuit serve anything else?).

[FlyingScot]

As another test you could disconnect the pump wiring (I assume its just a power connection?) and use this to switch a temporary relay.  You could then wire a feed directly from the battery via a fuse of the same rating as the car normally has, through the relay to the pump. 
 
If the fuse still blows then its the pump, if not then its something else on the circuit (does the fuel pump circuit serve anything else?).

Fuel pump is off the MFU on an SPI....

FS

[spiguy]

I've been in the situation where the pump was blowing fuses regularly. Eventually the pump died, and it was of course replaced. If you run the car low on fuel the pump can become uncovered and this can lead to issues such as this. The pump needs to remain immersed in fuel to keep it cooled, and on the later cars the gauge seems to reflect this need, as I find that it shows empty when there is still around 1/3 to 1/2 of the tank capacity remaining (determined by how much it takes to fill up to full under these conditions).

Edited by spiguy, 17 June 2017 - 12:06 AM.