Once upon a time, there was a Focus, a fuse, and a fuel pump ...

Follow up to last week's sad fuse-blowing saga ...

So, since replacing the fuse, it's been ok. Until tonight, that is. Very similar set of circumstances to last Friday. It was started outside home and then driven about seven miles. I was then in the first place for about

5 minutes, then back out and engine started again. Drove about 5 miles to next place, and stopped again for about 10 minutes this time. Back out, turned key and it started, only to chugg dismally before stopping.

Whipped up the bonnet and checked the fuel pump fuse. Yep, it had soft- blown again. Stuck a spare in and confidently turned the key. I didn't hear the pump run to pressurise the system. Tried a start anyway, but nothing. Rechecked the fuse, but still ok. Tried to get hold of my mate, but he wasn't playing, so had to call the missus to come and collect me. We left the car where it was in B&Q's car park. A few hours later, I had to go and pick her up from quite nearby, so I decided to swing by my car and give it one more go, on the basis that when the bad fuse was found and replaced last week, the car had been cooled for several hours.And guess what ? Yep, it started, and I drove it home perfectly ok. No fuse blowing. Didn't miss a beat.

So, here's my take on what's going on. Please feel free to fault my logic or make other suggestions.

As that fuse feeds nothing but the fuel pump, it's repeated failure must be associated with that circuit only. As the fuse is soft-blown rather than violently blown, that would tend to rule out any intermittent wiring short. The fact that the fuse *is* soft-blowing, indicates an excess current condition, which suggests the fuel pump itself. The fact that it happens when everything is well warmed up, and after two or three starts in close succession, and always at the turn on when the pump is going from stopped to run to pressurise the system, again suggests fuel pump. The fact that tonight when I replaced the fuse immediately after failure, the pump didn't run, but later when fully cooled down, it did, and ran normally, still further suggests the pump.

So, would you agree that the next move has got to be a replacement pump ? Obviously, we will look for chafed wires etc, but I'm not expecting to find any. Last point. I'm being told that the tank has to be dropped to replace the pump, due to Ford omitting to put an inspection cover over the tank's top access point for the pump, under the back seat. Is this true ? Is there any way to do the job without having to drop the tank ?

TIA

Arfa

Reply to
Arfa Daily
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Seems the next logical step.

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Chris

Reply to
Chris Whelan

Not sure I'd like to use a Dremel with just millimetres between the metal and the plastic fuel tank!

Is the floor expected to be sealed? I'm thinking of ingress of fumes from damaged exhaust etc, plus road noise (notice he removed the sound deadening undercoat). The pictures seem to show a fairly wide slot in the flap, and it doesn't look at all sealed. The original floor looks pretty much one piece, with a grommet doing a good job at sealing the cable hole.

Would removing part of the floor weaken the structure at all?

D
Reply to
David Hearn

for the trouble it is to do, and the rarity of the job, plus the potential risks, it really is not worth it. Removing tanks is usually easier than it looks at first glance.

Reply to
Mrcheerful

a thread on it here, seems to be not uncommon, I like the idea of damaged wiring near the pump:

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Reply to
Mrcheerful

In article , Arfa Daily scribeth thus

Thought the next bit would be you'd been wheel clamped and it was a 100 quid charge to free U!...

Bet its shorted turns somewhere in the motor that could cause all of what you've been describing..

Course you could try a sawn off Six inch nail to see what happens under extreme duress, but trouble is it won't fit the fuseholder;(...

Reply to
tony sayer
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These will:

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Chris

Reply to
Chris Whelan

I have seen those somewhere else recently, perhaps Maplins?

Reply to
Mrcheerful

have you tried bypassing the fuel pump relay? it is the green with an orange that feeds the fuel pump.

Reply to
Mrcheerful

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