Car won't start
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Discussion

anonymous-user

Original Poster:

77 months

Sunday 5th April 2015
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I had nice family trip planned in the Monaro this morning and the bloody thing won't start. Last week it came home from a service at Monkfish and was running fine but this morning it just cranks and cranks but won't catch. No smell of petrol and I cannot hear the pumps priming when I turn on the ignition, therefore I suspect something's amiss with the fuel system. I've just closed the garage door again and the bloody thing can stay there sulking.

It's never done this before, any ideas what to check/try before I call Mr AA man?

preciousmetal

3,373 posts

199 months

Sunday 5th April 2015
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Fuel pump Relay ?

anonymous-user

Original Poster:

77 months

Sunday 5th April 2015
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preciousmetal said:
Fuel pump Relay ?
I thought the same, or maybe a fuse. Where do I find that and how to check it?

stevieturbo

17,968 posts

270 months

Sunday 5th April 2015
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Do you have a scan tool etc to see if you have communications with the ecu ?

That should let you know if the ecu itself is receiving power ok without getting your hands dirty

After that, you'll need to access wiring to the pump and check for power on key on, and during cranking.

If not, checking wiring, fuses, relays etc Presumably you are no longer using OEM relays and wiring so these should be easier to trace and check

anonymous-user

Original Poster:

77 months

Sunday 5th April 2015
quotequote all
No, but scan gauges are all working fine. Which relay/fuse should I look at? Is there a way to test?

stevieturbo

17,968 posts

270 months

Sunday 5th April 2015
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wormus said:
No, but scan gauges are all working fine. Which relay/fuse should I look at? Is there a way to test?
You need to find the connector for the wiring to the pump, local to the pump and test there.

If you arent getting power there, then you can look further. As said, I would highly doubt...certainly hope you are not using the OEM relays and wiring for your fuel pump. So best to test at the pump first, and then work back.

davegreg

1,099 posts

212 months

Monday 6th April 2015
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This is what you want! wink

anonymous-user

Original Poster:

77 months

Monday 6th April 2015
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Just found a melted fuse which I guess indicates a problem!








Looks like the plastic around the fuse has boiled, needed a pair of pliers to get it out and it melted into the holder.

I'll see what Roger recommends before going further.

stevieturbo

17,968 posts

270 months

Monday 6th April 2015
quotequote all
Is that the fuel pump fuse ?

With some of the modern pumps about, or dual pumps a blade style fuse like that isnt always ideal whether it's within the current range or not.
They just draw lots of current and small blades will melt if run close to max load for long periods.

Even around 2/3 max load I'd be wanting to upgrade to a larger fuse or fusible link type of thing.

Plus lots of replacement fuses you buy these days are made in china crap which is almost impossible to avoid.

If you search egay etc for "maxi fuse holder" etc they do larger versions of the normal blade fuse which will tolerate the current better.

Edited by stevieturbo on Monday 6th April 15:34

anonymous-user

Original Poster:

77 months

Monday 6th April 2015
quotequote all
The fuse holder is in-line and the wire runs from the battery, towards the rear of the car. Looks suspiciously like the culprit.

I have twin pumps and a bit of Googling shows a 255 lph pump can draw up to 18 amps. It's a 20 amp fuse and looks more like it's melted than actually blown. I'll check with Roger but if my hunch is right, it hopefully just needs a beefier fuse/holder. Fingers crossed.

stevieturbo

17,968 posts

270 months

Monday 6th April 2015
quotequote all
wormus said:
The fuse holder is in-line and the wire runs from the battery, towards the rear of the car. Looks suspiciously like the culprit.

I have twin pumps and a bit of Googling shows a 255 lph pump can draw up to 18 amps. It's a 20 amp fuse and looks more like it's melted than actually blown. I'll check with Roger but if my hunch is right, it hopefully just needs a beefier fuse/holder. Fingers crossed.
255's arent as bad, but they can see 10-12A each. The bigger ones 340 and upwards can see as much as 20A each depending on pressure, the current they draw is insane.

My 044's draw around 22A normally, rising to about 26A at max pressure I'd use ( that's both pumps, not one ). Even this did hurt a 30A fuse slightly over time although it never got as bad as yours. You could just see it had been affected by heat
I try and use OEM fuses taken from factory cars whether scrap yard etc though. They will always be better quality than the chinese stuff.

But the standard blades just arent enough really. Switch it to a maxi blade and stick a 30A fuse in it if it is doing both pumps.

Cheap fix.


Edited by stevieturbo on Monday 6th April 16:20

anonymous-user

Original Poster:

77 months

Monday 6th April 2015
quotequote all
Cheers Stevie. Just bought a new 100 amp maxi fuse holder and what I hope are some decent quality fuses: http://www.amazon.co.uk/dp/B000T6BH2A/ref=pe_38572...

stevieturbo

17,968 posts

270 months

Monday 6th April 2015
quotequote all
wormus said:
Cheers Stevie. Just bought a new 100 amp maxi fuse holder and what I hope are some decent quality fuses: http://www.amazon.co.uk/dp/B000T6BH2A/ref=pe_38572...
The fact the holder etc is bigger and designed for more current, it should negate a lot of the quality issues simply as you arent pushing the connector near its limits.

So it should be fine with the new setup



S800VXR

5,877 posts

223 months

Monday 6th April 2015
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What on earth were you thinking!!?? Use the Ro..... On the road. For God sake man!

shunter V8

788 posts

188 months

Monday 6th April 2015
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Bad news Paul,cut out the fuse link and splice in some barbed wire,that will not melt.idea. We are going to monkfish on Thursday for the annual check up.

bigwheel

1,634 posts

237 months

Monday 6th April 2015
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Got to hope the wire gauge is heavy enough to feed the pumps.

ARAF

20,759 posts

246 months

Tuesday 7th April 2015
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bigwheel said:
Got to hope the wire gauge is heavy enough to feed the pumps.
I wonder if there's a fault in one of the pumps, causing it to draw too much current.

stevieturbo

17,968 posts

270 months

Tuesday 7th April 2015
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ARAF said:
I wonder if there's a fault in one of the pumps, causing it to draw too much current.
Doubt it, just the small fuse/holder isnt up to the job

MyM8V8

9,468 posts

218 months

Tuesday 7th April 2015
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shunter V8 said:
Bad news Paul,cut out the fuse link and splice in some barbed wire,that will not melt.idea. We are going to monkfish on Thursday for the annual check up.
Aaahhh. You're the guy that puts bolts for fuses in three pin plugs? wink;)

anonymous-user

Original Poster:

77 months

Tuesday 7th April 2015
quotequote all
shunter V8 said:
Bad news Paul,cut out the fuse link and splice in some barbed wire,that will not melt.idea. We are going to monkfish on Thursday for the annual check up.
I'm getting the bumper painted tomorrow and was thinking of jamming a paper clip in the holder so I can start and move the car, probably not a good idea though? smile

By the way, I'm coming over for race week with Alex and the kids if you and Andrea fancy meeting up?