no power to fuel pump

volvobm · Jun 11th, 2024, 18:35

evening
Im looking for help / ideas on what could cause my in tank fuel pump to no have power going to it ?
new pump fitted .new green relay fitted
took it out and tested the pump on the bench , it works
but in the car ...No

Forrest · Jun 12th, 2024, 02:04

The radio interference suppression relay and the crank position sensor can also go faulty and lead to no fuel.

Rversteeg · Jun 12th, 2024, 09:43

Assuming it is a 940, check fuse no. 11. This fuse is between the fuel pump relay and the fuel pump. If there is no power on this fuse during cranking, there is something wrong with either the fuel pump relay or the wiring between relay and fuse. If there is power on this fuse during cranking, the fault must be in the wiring between fuse box and fuel pump.
If the tacho needle is moving during cranking, the crank position sensor and radio suppression relay are fine.

volvobm · Jun 12th, 2024, 12:48

taco needle bounces about 5 mm
fuse 11 is good
the pump works on the bench when connected to a battery
its an 88 740 b230E

Rversteeg · Jun 12th, 2024, 17:19

I would run a temporary wire from fuse 11 to the fuel pump connector to rule out a faulty wire.

Offgrid · Jun 12th, 2024, 19:18

I've got a similar problem on my B200E, but I've got no spark and no tacho jump. I've had 2 740s fail due to a faulty fuel pump relay, but I don't think that affects the lift pump. Please correct me if I am wrong. I'm about to take my pump out, but I've been waiting for a fancy tool to remove the retaining ring.

volvobm · Jun 12th, 2024, 21:10

my fancy tool was a rubber mallet and either a piece of wood or the bar from a jack . you don't want to put anything sharp on it . and find yourself a good work position
ive had mine in and out 20 times now . Vaseline is a must

360beast · Jun 12th, 2024, 22:04

Quote:

Originally Posted by volvobm

my fancy tool was a rubber mallet and either a piece of wood or the bar from a jack . you don't want to put anything sharp on it . and find yourself a good work position
ive had mine in and out 20 times now . Vaseline is a must

Same here, a blunt instrument being massaged with a hammer does the job.

Forrest · Jun 13th, 2024, 02:20

There is a good guide on the Skandix website which was what I mostly followed, at least getting the pump out.

https://www.skandix.de/en/documents/...-tank/3000438/

And yes, +1 for the block of wood and mallet “special tool”.

NI_Volvo_Nut · Jun 26th, 2024, 13:24

The earth wire had corroded off the tank unit on my Volvo.

Have you actually checked for voltage and earth at the tank??

Jun 11th, 2024, 18:35	#1
volvobm Member Last Online: Jun 12th, 2024 21:13 Join Date: Oct 2007 Location: Dublin	no power to fuel pump evening Im looking for help / ideas on what could cause my in tank fuel pump to no have power going to it ? new pump fitted .new green relay fitted took it out and tested the pump on the bench , it works but in the car ...No

Jun 12th, 2024, 09:43	#3
Rversteeg Master Member Last Online: Jun 28th, 2024 11:26 Join Date: Feb 2006 Location: Amersfoort (NL)	Fuse 11 Assuming it is a 940, check fuse no. 11. This fuse is between the fuel pump relay and the fuel pump. If there is no power on this fuse during cranking, there is something wrong with either the fuel pump relay or the wiring between relay and fuse. If there is power on this fuse during cranking, the fault must be in the wiring between fuse box and fuel pump. If the tacho needle is moving during cranking, the crank position sensor and radio suppression relay are fine.

Jun 12th, 2024, 12:48	#4
volvobm Member Last Online: Jun 12th, 2024 21:13 Join Date: Oct 2007 Location: Dublin	taco needle bounces about 5 mm fuse 11 is good the pump works on the bench when connected to a battery its an 88 740 b230E Last edited by volvobm; Jun 12th, 2024 at 12:50.

Jun 12th, 2024, 17:19	#5
Rversteeg Master Member Last Online: Jun 28th, 2024 11:26 Join Date: Feb 2006 Location: Amersfoort (NL)	Test wire I would run a temporary wire from fuse 11 to the fuel pump connector to rule out a faulty wire.

Jun 12th, 2024, 19:18	#6
Offgrid Offgrid camper Last Online: Jul 1st, 2024 09:13 Join Date: Apr 2022 Location: Havant	I've got a similar problem on my B200E, but I've got no spark and no tacho jump. I've had 2 740s fail due to a faulty fuel pump relay, but I don't think that affects the lift pump. Please correct me if I am wrong. I'm about to take my pump out, but I've been waiting for a fancy tool to remove the retaining ring. __________________ Cinderella ( Cinders ) - 1988 Volvo 740 saloon with B230E engine The Hoe - 1990 Volvo 740 estate with B200E engine The House - 2005 LDV Convoy hightop with Ford Transit turbo engine. Save Old Cars

Jun 12th, 2024, 02:04	#2
Forrest VOC Member Last Online: Today 12:24 Join Date: Feb 2008 Location: Gloucester	The radio interference suppression relay and the crank position sensor can also go faulty and lead to no fuel.

Jun 12th, 2024, 21:10	#7
volvobm Member Last Online: Jun 12th, 2024 21:13 Join Date: Oct 2007 Location: Dublin	my fancy tool was a rubber mallet and either a piece of wood or the bar from a jack . you don't want to put anything sharp on it . and find yourself a good work position ive had mine in and out 20 times now . Vaseline is a must Last edited by volvobm; Jun 12th, 2024 at 21:13.

Jun 13th, 2024, 02:20	#9
Forrest VOC Member Last Online: Today 12:24 Join Date: Feb 2008 Location: Gloucester	There is a good guide on the Skandix website which was what I mostly followed, at least getting the pump out. https://www.skandix.de/en/documents/...-tank/3000438/ And yes, +1 for the block of wood and mallet “special tool”.

Jun 26th, 2024, 13:24	#10
NI_Volvo_Nut Volvologist Last Online: Jul 1st, 2024 13:21 Join Date: Aug 2008 Location: Bangor - Norn Iron View Photos By: NI_Volvo_Nut	The earth wire had corroded off the tank unit on my Volvo. Have you actually checked for voltage and earth at the tank?? __________________ What's the matter with the car I'm driving? Can't you tell that it's out of style? Should I get a set of white wall tires? Are you gonna cruise the miracle mile?

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