Non start S3 fuel pump not priming

[brow]

I read a recent thread with hope it would cure my fault but alas no. please help.

The relay was my 1st thought (Yellow?) but matched a new one with no joy. Have i changed the right one?
With the ignition on i'm getting voltage at the fuel pump which makes me think my pump has failed but i want to be sure before changing it.

I've noticed a fuel injection relay (brown?) but motor factors can't match but ford might help. Could this cause the failure?

Your advice please oh wise men of the S Series

[tvrgit]

Right there is voltage at the fuel pump but the pump isn't working at all?

Test 1. Check the fuel pump earth - it won't work without a complete circuit.

Test 2. You have got the feed and earth on the correct way round, right?

Test 3. Run a live straight from the battery to the pump positive. WATCH FOR SPARKS!!!!

Test 4. Run an earth fly lead from the pump to the chassis.

If none of that works, it's the pump.

If it flickers into life during test 3 or 4, it's the wiring / fuses or something.

If it explodes in a ball of fire, it wasn't my idea.

[brow]

Cheers. I will run suggested checks and report back.

[bridgdav]

I had the same on mine last year..

Def' the wiring - earth and connections on the pump, cleaned them all up, used a small 9V block battery to kick off the pump and test it, put it all back together...

Hey Presto.

Should really strip all the wires back and replace the connectors with new.. But, I want to keep the car standard. ..

Or is it haven't got round to it yet..?

[brow]

Just returned from a frustrating few hrs trying fix this non start problem.

I just tested the following :-
1. Fuse - OK
2. Relay - replaced but getting 8v input but only 0.15v output (?)
2a. found pump connections very loose but not cause of problem.
3. pump end getting same 0.15v
4. connected battery direct to pos, on pump - nothing
5. connected known earth and direct battery to pump - nothing
6. just jumpered 87 & 30 (switch) on relay and pump contiunally ran.

So the pump works but not throught the new relay. I'm lost and its driving me insane!

Any further advice would be marvellous.

Edited by brow on Saturday 10th May 15:52

[pringli]

immobiliser cct? Can you hear (or feel) if the relay operates when you switch or an accomplice switches on the ign.?

Edited by pringli on Saturday 10th May 16:46

[Barkychoc]

Is there an impact / crash sensor anywhere on the S? The V8 has one under the bonnet, with a reset button.
Just a thought.

Chris

[pringli]

not that Ive found............................yet

[clarenceboddiger]

Those voltages seem a bit odd
a few things to think about
1) are you reading that voltage from the outgoing side of the coil to earth.
2) are you trying to run the pump in series with the relay coil
I know most relays are similar, but TVR did use relays with different contacts on the Indicator relay in relation to Generic ones, they may have done it on this relay too, this linkwill explain better

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[pringli]

Nathan, how are you getting on with fuel pump problem?

[brow]

Thanks all thus far. I will check the terminals on my new relay are going to the same connections / numbers as my original.

How do i test if the immobiliser is causing a problem?

[pringli]

provide a 12v+ positive to the relay terms as per Cider andys info. Thereafter its a case of bypassing that cct on the immobiliser, which depending on your confidence and ability may be best done by a electrical specialist.