VZ Fuel Pump Problems

[Harris]

I got my car back from the tuners a couple weeks ago and when i got it back the fuel pump relay was ticking really loud and gets very hot. Just wondering why this is happening and is the pump on its way out. It might have hurt it reving up on the dyno. What kw are the standed fuel pumps rated for? Any help would be good.

[bcw61]

I got my car back from the tuners a couple weeks ago and when i got it back the fuel pump relay was ticking really loud and gets very hot. Just wondering why this is happening and is the pump on its way out. It might have hurt it reving up on the dyno. What kw are the standed fuel pumps rated for? Any help would be good.

Not entirely sure what you mean by the fuel pump relay 'ticking' really loud........however:

It's possible your fuel pump relay may have damaged/corroded relay external connection tabs (where it plugs into the relay holder). I have had similar issues with relays in other Commodores.

Try cleaning the relay terminals, ensuring that that make good contact with the relay holder terminals. I would suggest that if the fuel pump was drawing excess current (causing the relay to get hot), then the fuse would eventually melt.

Failing that, is it possible that your fuel pump was run with a very low fuel level? The pumps rely on a volume of fuel, both to provide lubrication of the bearings, and to keep the motor windings cool.

[Harris]

Ok i will give them a clean and see how it goes but it couldnt have been low on fuel because i droped it off at the tuners with a full tank of fuel and it came back just passed half empty. What kw are the standed fuel pumps rated for?

[Harris]

Got it checked out and the guy said there is a volt drop to the relay and it is only picking up 7 volts. He said there could be a problem in the computer making it do that. Has anyone seen this before or is there another reson it could be getting volt drop.

[RiCeY]

7 volts where? Relays have a low voltage and high voltage circuit, one is the signal to turn the relay on and off, and one is the switch to allow current to pass through.

[Macca87]

In this situation there should be 12v on both the coil and the contacts, the relay is a control for high current circuits not hight voltage controlled by low voltage. The 7v that are present would be causing the chatter because it isn creating enough magnetic force to keep it engaged. If it is controlled by the computer and you just got it tuned I would go back to the tuner and ask him want he has done to it and get him to fix it

[Harris]

Will make shore it is the computer and then take it bac to the tuner. Is there much chance of it just being my bad luck have there been any other commodore computers do this?

[Macca87]

It would be a first to hear it but anything is possible. Do a quick swap of relays (your flog light relay should be the same) just to make sure it's not the relay also check your ground to make sure there isn't voltage on it (should be 0). What part of Perth are you from?

Disclaimer: I am not a mechanic I am an elecrtician, advise given is only I guide base on what I have been to and my limited knowledge of specifics in regards to cars

[Harris]

Have swaped the relays and still has the humming sound. Got the auto electrition to have a look and he told me he thinks its dropping somewhere in the computer but hes goin to check it out and see if there is any other place it could be going. The car is displaying service reminder on the dash and i looked it up in the book and it said it had something to do with emissions. Could that be related to the relay ticking?

[Macca87]

No the emissions error would be that the computer isn't liking what the O2 sensors are reading it shouldn't affect the fuel pump relay that side of things is more injectors and fuel pressure control in relation to air charge

[Harris]

So it sounds like it needs to go back to the tuner and get all these problems fixed?

[Macca87]

Yeah that's my best recommendation