Dead fuel pump relay? - dead car!!

[Dr. Rog]

A little help needed here urgently if you please.

This morning (Thursday) I was almost at work when the engine cut out, nice and sweet, no drama just dead.

Well the lack of steering and brakes is not without drama but I knew to stop before I used up the vacuum.

Called the AA who where pleasantly prompt and I had a chap old enough to remember 900s. He turned the key and it fired up straight away. (curses)

Remembering that the fuel pump relay is a common fault he popped it out and examined it carefully, noting a potentially dodgy solder joint he re-soldered it and put it back in. All was fine for half a mile when it conked out again. AA's finest then spent 20 minutes trying to get it to fail again without success, so I drove six miles home without a problem and we put in the relay from my old car, which had had a similar fault once. The "new" relay was date-stamped 2006, not new but not old at all.

Drove back to work, without a tail, without problem. After an abbreviated days work I got in the car .. and it would not start

Got AA out again. he tried lots of things, the 4 wires to the pump/sender has only one wire with a voltage - 5V. Also "battery feed (ign) at coil [is] not switching, fuel pump fuse powering up when cranked"

Fairly satisfied it was the relay and that he didn't have one he towed us out of "site" before we where locked in and we went and had a take-away whilst waiting for the Relay truck. Got home at 8:00 three hours late.

Does this sound like the fuel pump relay? (the white one).
Is there a fault that takes them out? Could I have destroyed two?
Any help welcome.

[Steve940estate]

Hi
Common causes of cutting out are :-

Crank position sensor. Faulty sensor , wires or connector.

Fuel injection relay. Located on the passenger side of your car above the battery.

Ignition Switch. I have read that these can sometimes play up.

Apart from that is it possible that the fuel pump itself has a bad connection ? I seem to remember you had to do something with it a while back.

[Dr. Rog]

This thread is exactly what happened to me the first time

http://www.volvoforums.org.uk/showth...uel+pump+relay

I am too tired to do any soldering tonight

[RealEstate]

Can you induce the fault by wiggling the fuel relay with your finger when the engine is running? If yes maybe the fuel relay socket.

Have you cleaned the fuses esp fuel fuse (top left IIRC)?

[rogerthechorister]

My B234F played this game on me just the other day. The white and the green fuel pump relays (on different ages) are different - i am talking about the white. If you remove the relay, take the cover off, and re-insert it, you can just get at the moving arm with your little finger although the front half is harder than the rear half. It was possible to start the car with one hand on the relay and then once in third or top drive with a finger in there ready to wiggle(evening ossifer) if needed.

One from Volvo is only £27, and pattern ones allegedly new about half that. Relay contacts do go off during non-use. It might be possible to use emery cloth to clean the contacts, or switch cleaner, but the sensible thing to do is to put a new relay in.

[brodgar]

have you tried bypassing the relais??????

if you want to do it nicely-- put a on/off switch in the bypass.



1==== if the car behaves well with the bypass than it means it is the relay

-- with the switch installed you can drive the car normally till
you have a relais


2=== if car doesnt behave well- than it is perhaps pump as it should work
continous with direcvt current on it




3=== if not 2 than continue faulttracing

[rogerthechorister]

http://cgi.ebay.co.uk/ws/eBayISAPI.d...=STRK:MEWAX:IT

[Dr. Rog]

Originally Posted by RealEstate

Can you induce the fault by wiggling the fuel relay with your finger when the engine is running? If yes maybe the fuel relay socket.

Have you cleaned the fuses esp fuel fuse (top left IIRC)?

No, we couldn't. The AA chap spent ages getting the tray out ( it took three hands) and he poked all the contacts.

Fuse also checked. I might clean it better.

There is a lot of evidence it is the relay. I will try and get one today.

Is it worth getting the crank sensor as well? bearing in mind the symptoms.
Also is there other likely faults that could induce relay failure, or are they just crap?

[Steve940estate]

My car had an intermittent start problem. It would turn over just wouldn't fire.
I needed the car to be reliable so I changed the crank sensor and fuel injection relay at the same time. I haven't had a problem since (fingers crossed) so don't know which one was faulty.

I think the thing with the crank sensor is that if they do play up it just shuts everything down. If the engine cranks over but there is no movement in the rev counter it's what I would say is wrong. Job to tell what happens when driving at speed. Fortunately it didn't happen to me.

It may be worth undoing the plug and connecting it again (relays and connectors as well ) just in case it's a bad connection.

[Dr. Rog]

£40 white relay did not fix the problem!!

used the old relay to test. The coil nearer the front of the car tends to latch on, with or without the ignition on. The one nearer the back makes the pump hum.

I suspect this is not now my problem

I will try the others on the list.