Volvo 740 failing to start

Hi, I'm new to this forum.

We are living in England and have a petrol Volvo 740 Estate automatic.

Recently it's been reluctant to start on cold days. Our initial thought was ice in the fuel so we added something to dry out any water in the fuel. The engine was turning over fine but failing to start.

This week the problem has begun happening when the car is warm as well as cold.

We were able to drive into town 2 days ago, parked for 10 minutes, then the car failed to start with a warm engine. The breakdown chap said it wasn't an ignition problem as it was turning over fine. However he gave us a boost that did enable the car to start. He said everything pointed to fuel pump relay.

We later changed the fuel pump relay on Monday as this is apparently a common fault in Volvos. It then began starting intermidently and would start on the second attempt. This morning again it failed to start. Each time we try to start it we hear the in-tank fuel pump doing its thing so I don't think it's that. Incidentally we took the case off the old relay and couldn't see any cracks.

It feels very much like a problem to do with not enough fuel getting through to initially start the car.

I have to stress that once we finally get the thing started it runs very nicely and doesn't stall or misfire at all. This must surely rule out lots of common problems.

Any advice, or anyone had anything similar? We have 6 children (one of whom is a baby) and really rely on the car on a day to day basis for transport.

Yvonne

 

Hi
I owned a 740 a couple of years ago,and had the same problems.
In my case it was the relays yep two of them one under the hood and the other in dashboard console and for me it worked fine for some time but I also had to fix the electric
connections on the mainpump but after all that it worked just fine
It would not hurt if you check the pump in the gastank too

I hope this is some help
Regards
Nightmare
"Yvonne and Dan" <> skrev i meddelandet Hi, I'm new to this forum.

We are living in England and have a petrol Volvo 740 Estate automatic.

Recently it's been reluctant to start on cold days. Our initial thought was ice in the fuel so we added something to dry out any water in the fuel. The engine was turning over fine but failing to start.

This week the problem has begun happening when the car is warm as well as cold.

We were able to drive into town 2 days ago, parked for 10 minutes, then the car failed to start with a warm engine. The breakdown chap said it wasn't an ignition problem as it was turning over fine. However he gave us a boost that did enable the car to start. He said everything pointed to fuel pump relay.

We later changed the fuel pump relay on Monday as this is apparently a common fault in Volvos. It then began starting intermidently and would start on the second attempt. This morning again it failed to start. Each time we try to start it we hear the in-tank fuel pump doing its thing so I don't think it's that. Incidentally we took the case off the old relay and couldn't see any cracks.

It feels very much like a problem to do with not enough fuel getting through to initially start the car.

I have to stress that once we finally get the thing started it runs very nicely and doesn't stall or misfire at all. This must surely rule out lots of common problems.

Any advice, or anyone had anything similar? We have 6 children (one of whom is a baby) and really rely on the car on a day to day basis for transport.

Yvonne

 

Hi, I'm new to this forum.

We are living in England and have a petrol Volvo 740 Estate automatic.

Recently it's been reluctant to start on cold days. Our initial thought was
ice in the fuel so we added something to dry out any water in the fuel. The
engine was turning over fine but failing to start.

This week the problem has begun happening when the car is warm as well as
cold.

We were able to drive into town 2 days ago, parked for 10 minutes, then the
car failed to start with a warm engine. The breakdown chap said it wasn't an
ignition problem as it was turning over fine. However he gave us a boost
that did enable the car to start. He said everything pointed to fuel pump
relay.

We later changed the fuel pump relay on Monday as this is apparently a
common fault in Volvos. It then began starting intermidently and would start
on the second attempt. This morning again it failed to start. Each time we
try to start it we hear the in-tank fuel pump doing its thing so I don't
think it's that. Incidentally we took the case off the old relay and
couldn't see any cracks.

It feels very much like a problem to do with not enough fuel getting through
to initially start the car.

I have to stress that once we finally get the thing started it runs very
nicely and doesn't stall or misfire at all. This must surely rule out lots
of common problems.

Any advice, or anyone had anything similar? We have 6 children (one of whom
is a baby) and really rely on the car on a day to day basis for transport.

Yvonne

********************************************************************

I agree that the original problem has all the characteristics of a bad fuel
pump relay. Glad you changed it.

The starting on the second try raises the likelihood that the fuel pressure
in the injector rail is bleeding off. The usual way to diagnose that (other
than putting a fuel pressure guage on the rail) is to use a different
starting technique. Try this: "bump" the starter (crank for a fraction of a
second), let the key back into the "run" position for a couple seconds, then
try starting. If it starts reliably that way, the pressure is probably
bleeding off... usually back through the check valve on the output of the
main fuel pump under the car beneath the left front seat. Mine has been
doing that for years and I just use the bump/start method. That's how lazy
I've become.

There is a related possibility. One of the fuel injectors may be dripping
into the intake, which floods one cylinder and causes the others to have the
symptoms above.

In either case, a bottle of fuel injector cleaner (as opposed to the fuel
drying additive) is cheap, easy, and can't hurt. It may fix either problem
by the time the tank of fuel is used up. If not, you're out a couple of
pounds.

I have no idea why it is so hard to start an engine that has lost pressure
in the fuel rail, but maybe the injection computer gets confused and tries a
leaner mixture about the time the pressure comes up.

Mike

 

Why not contact the Volvo Owners Club forums for advice on your problem. URL is http://www.volvoclub.org.uk On the index page there is a link on the left hand side for Forums. Click on that and register yourself as a forum user. Then you can access the forums. Technical problems for your car would be under "700 series". Also the Brickboard FAQs are accessible from the VOC site. Same URL, link also on index page. The main problems with 740s are the fuel system & ECU (both pumps, fuel pump relay and radio suppression relay [this actually should be named as injector relay as it is part of the circuit for all the injectors] and the ignition system & ICU ( timing sensor(s), distributor, coil and leads, spark plugs and ignition amplifier [this drives the coil, but sits between the air filter and the left hand inner wing] which usually suffers from corrosion and poor connections, mainly earthing ones.

It only costs about £25 per year to join the VOC, this can also be done from the VOC site via a link on the index page.

All the best, Peter.

700/900/90 Register Keeper,
Volvo Owners Club (UK).
Hi, I'm new to this forum.

We are living in England and have a petrol Volvo 740 Estate automatic.

Recently it's been reluctant to start on cold days. Our initial thought was ice in the fuel so we added something to dry out any water in the fuel. The engine was turning over fine but failing to start.

This week the problem has begun happening when the car is warm as well as cold.

We were able to drive into town 2 days ago, parked for 10 minutes, then the car failed to start with a warm engine. The breakdown chap said it wasn't an ignition problem as it was turning over fine. However he gave us a boost that did enable the car to start. He said everything pointed to fuel pump relay.

We later changed the fuel pump relay on Monday as this is apparently a common fault in Volvos. It then began starting intermidently and would start on the second attempt. This morning again it failed to start. Each time we try to start it we hear the in-tank fuel pump doing its thing so I don't think it's that. Incidentally we took the case off the old relay and couldn't see any cracks.

It feels very much like a problem to do with not enough fuel getting through to initially start the car.

I have to stress that once we finally get the thing started it runs very nicely and doesn't stall or misfire at all. This must surely rule out lots of common problems.

Any advice, or anyone had anything similar? We have 6 children (one of whom is a baby) and really rely on the car on a day to day basis for transport.

Yvonne

 

Thanks very much for your helpful posting, and the other two people who
posted too.

The problem turned out being water in the fuel which on cold days had turned
to ice. The local garage removed a lot of water from the bottom of the tank
and from the fuel injector rail.

Having had a couple of cold days where the car has started we're now fairly
convinced that was the problem.

Looks like we could do with new spark plugs and distributor cap anyhow.

Thanks again for your reply to my original.

Yvonne

 

Aha water in the fuel good it turned out well
Regards
Nightmare