HELP !!! Fuel pump = breakdown
HELP !!! Fuel pump = breakdown
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S2 Giles

Original Poster:

2,871 posts

304 months

Sunday 16th October 2005
quotequote all
Hi

I hadnt used the S2 for a week or so and so went out for a blast, fine until it died shortly after filling up the tank..... luckily i was within walking distance of home. I got assistance of the pushing variety to get me back home.

So now i have a dead fuel pump..... no clicking from it at all. I have checked the 25amp fuse which seems ok and the yellow relay is still clicking (once when ign switched on and then again about 4 seconds later).

Should I assume this is all ok and suspect the fuel pump is knackered ? or is the relay misbehaving ? whats my next move ?

Ive searched historic threads but i'm still not sure.

Thanks again
Giles

Pies

13,116 posts

285 months

Sunday 16th October 2005
quotequote all
IIRC you can take a live feed direct to the fuel pump.This will tell you if its the fuel pump or relay

Also if it runs you can get the car home

HTH #

IIRC Green V8s posted the above a while back

Le TVR

3,097 posts

280 months

Monday 17th October 2005
quotequote all
S2 Giles said:

So now i have a dead fuel pump..... no clicking from it at all. I have checked the 25amp fuse which seems ok and the yellow relay is still clicking


Should be the pink relay for the fuel pump. They are far more unreliable than the pumps.

Pull the pink relay and see if you are getting any volts from it and that none of the pins are loose. Usually the relay inside suffers from poor solder joints to the PCB. No big job to pull the cover of the relay and resolder everything.

S2 Giles

Original Poster:

2,871 posts

304 months

Monday 17th October 2005
quotequote all
Next stage in the mini sga. I have wired up a battery to the pump & the pump works just fine ! so it must be the relay that needs replacing or fixing.

However mine is not pink, it is bright yellow and so is the holder it plugs into, this is the correct relay isnt it ?

Cheers

silverback mike

11,293 posts

282 months

Monday 17th October 2005
quotequote all
Just done the same myself.
Yellow connections

In my case it was the connector to fuel pump that had corroded, making the car die on me.

GreenV8S

31,014 posts

313 months

Monday 17th October 2005
quotequote all
Not to worry you Silverback, but ...

I had the same symptoms which were fixed by replacing the relay, then came back and were fixed by replacing a badly frayed wire at the connection to the pump, then came back and fixed by cleaning up and recrimping the relay socket, then came back and were finally fixed for good by removing the pile-o-rust (tm) inertia cut-out switch. All the problems I fixed were genuine problems that were contributing to the general reliability, perhaps provoked by me disturbing things while I was tracking down the original problem. Amazing how things that couldn't possibly have worked will be fine until you take a good look at them.

Trefhead

96 posts

267 months

Monday 17th October 2005
quotequote all
top tip....On the S1 anyway....Cable tie in your fuel relay. On my old S1, because it constanly worked loose (and the old girl would fuel starve) the terminals would arc out and the plastic housing melted and it had to be rewired. As the fuse carrier with the relays was designed for Ford to be horizontal and they are set vertically on the S1 the first job I did on my 'new' one was the cable tie job on each relay. Another weakness is the fuse box can get wet from leakage aroung the near side bonnet catch which also leads to arcing,,

Le TVR

3,097 posts

280 months

Tuesday 18th October 2005
quotequote all
yellow??

Obviously the person fitting the relays is as colour blind as the one making the wiring looms

Anyroadup you can pull the cover on the fuelpump relay and plug it back in if no connections are loose or cracked. Ign on and manually close the relay. If pump runs you probably have an ignition pulse sense missing. If it doesnt run you have a supply failure.

Hoover33

5,993 posts

271 months

Tuesday 18th October 2005
quotequote all
Is the battery in the car dead ??????

I had a simalr problem....... which eventually traced back to a dead battery..... which I had used not more the 30 mins before the non start.

S2 Giles

Original Poster:

2,871 posts

304 months

Wednesday 19th October 2005
quotequote all
Ok so the saga continues. I bought a new fuel pump relay (yellow) from Ford for just £10. Fitted the item & it clicked a bit but eventually worked, then it didnt & then it did again.

Now its settled and seems to be working fine......BUT ive put the old relay back in and that now works fine too !!!!! help !!!!!!!

I have either reset the system somewhere by plugging in the new relay, or i have another problem elsewhere.

Can anyone help....what should i do ?

silverback mike

11,293 posts

282 months

Wednesday 19th October 2005
quotequote all
Have you checked the connector just prior to the fuel pump - look under the car near to the rear nearside wheel) it is a white multiplug connector.
If the contact or plug has broken down it will present those symptoms, and would explain the fact sometimes it starts, sometimes it doesn't.

Colin Blues2

2,541 posts

286 months

Wednesday 19th October 2005
quotequote all
Sounds to me like a loose connection in the loom probably one of the ones into the relay holder.

Especially now you've put the old one back and it is working.

Colin

GreenV8S

31,014 posts

313 months

Wednesday 19th October 2005
quotequote all
You can keep trying bits and pieces, but I know how frustrating it can be to have a car that keeps letting you down. If the problem is proving tricky then I suggest you wire up a seperate fused supply from the battery to the pump. Bring a wire back from the pump and connect a bulb inside the car to it so you can see when the original supply drops out. And just drive around as normal. When it does drop out, be ready with the multimeter to work out where the power is getting lost. I made up a 'Y' lead to let me plug the original relay in one socket and then probe the other to see whether the relay coil was still being energised and whether there was any voltage drop across the contacts, working out from there. You could get away without this by back-probing the socket but it just made it easier. You need to be ready with a specific test because the problem is likely to come and go, but each time it comes back you can get that bit closer to pinning it down. It's a bit tedious, but very rewarding when you finally get it.

Le TVR

3,097 posts

280 months

Thursday 20th October 2005
quotequote all
S2 Giles said:
Fitted the item & it clicked a bit but eventually worked, then it didnt & then it did again.



From the symptoms it sounds like a supply fault. If its clicking the fault is not on the pump side.
If the clicking is fairly quick I'd go for the supply to the relay. If the clicks were always several seconds apart check the ignition pulse feed from the coil.
Oh, and not forgetting the earth return for the relay....

S2 Giles

Original Poster:

2,871 posts

304 months

Thursday 20th October 2005
quotequote all
Thanks so much for the responses. I dont know what i'd do without this forum but I am learning alot and i'm not what i'd call a novice.

Tonight I took her out with the new relay in place.... in the pitch black lanes on a fast bend doing 70, i suddenly lost all my lights !!

I traced this back to the fuse holder & a piece of exposed wire that was shorting out against the ECU cover & blowing the headlight fuse.

Fixed that problem. However the fuel pump is now behaving itself, no matter how many times i switch her off & on or leave her running.

Ive just lost confidence now, i'm waiting for her to do it again so i can have another go at tracing the problem.

Anyway, thanks again for the comments

LeeBee

773 posts

313 months

Sunday 30th October 2005
quotequote all
Might also be worth checking the little diode that sits next to the small brown rectangular relay (in the loom on the passenger side), I think this diode is used instead of a fuel inertia cutoff switch

Cheers

LeeBee

LeeBee

773 posts

313 months

Sunday 30th October 2005
quotequote all
Might also be worth checking the little diode that sits next to the small brown rectangular relay (in the loom on the passenger side), I think this diode is used instead of a fuel inertia cutoff switch

Cheers

LeeBee

S2 Giles

Original Poster:

2,871 posts

304 months

Sunday 30th October 2005
quotequote all
Cheers folks

At present she is behaving herself, so i'm going to keep using her daily & see what happens.

Giles