i had to change the in tank fuel pump on my 740t, now the car starts every time but dies straight away, ive had the pump back out and tested it and it works, dunno if its a co-oincidence but i also changed the leads. dizzy/rotor arm whilst in the middle of doing the pump but i thought any problem there would cause rough running, doing my head in now as running out of free retest time, and you also have to be double jointed to do this job
Could be the fuel pump relay mate, ive just sold one of these to a customer who had exactly the same issue, and it sorted it
[QUOTE=merc85;700829]Could be the fuel pump relay mate, ive just sold one of these to a customer who had exactly the same issue, and it sorted it[/QUOTE] on a 740?
[QUOTE=T5frankie;700833]on a 740?[/QUOTE] yes a blue 740 turbo intercooler estate, Manual too :)
these are really common as a breakdown. i thought it was a green relay behind radio area. but may be blue in colour.
[QUOTE=AAnickmac;700839]these are really common as a breakdown. i thought it was a green relay behind radio area. but may be blue in colour.[/QUOTE] The one the gentleman had in my shop was a white relay, cant remeber the part number of it tobe honest.
i know its common on 850's, will try that dunno why it should suddenly go as i change the pump though
[QUOTE=merc85;700829]Could be the fuel pump relay mate, ive just sold one of these to a customer who had exactly the same issue, and it sorted it[/QUOTE] [QUOTE=merc85;700842]The one the gentleman had in my shop was a white relay, cant remeber the part number of it tobe honest.[/QUOTE] I hope you're not pushing your business. ;)
[QUOTE=T5frankie;700844]i know its common on 850's, will try that dunno why it should suddenly go as i change the pump though[/QUOTE] may be your new pump is drawing more power though the old relay than the old tired one did....just a thought
[QUOTE=stribo;700847]I hope you're not pushing your business. ;)[/QUOTE] no im not, but as a registered trader on here, if i feel the need to i can. :)
[QUOTE=stribo;700847]I hope you're not pushing your business. ;)[/QUOTE] stirrer.......lol
Yeah the relays are bad had the same problem on the 240 but in my case it wouldn't start a quick bash to the relay and it would be fine its the solder inside of them that goes dry I re soldered mine and was all fine. One thing to do frank is get some one to start it while you listen for the pump and see if it cuts out once its started
[QUOTE=MoleT5-R;700849]may be your new pump is drawing more power though the old relay than the old tired one did....just a thought[/QUOTE] i tried the new one and the old one as it wasnt actually the pump that went just rusted through joints, they both work, i ran a live straight from the battery to the pump worked but still didnt stay running
[QUOTE=T5frankie;700854]i tried the new one and the old one as it wasnt actually the pump that went just rusted through joints, they both work, i ran a live straight from the battery to the pump worked but still didnt stay running[/QUOTE] so if I'm reading this right, you've got 2 duff pumps then ??
[QUOTE=MoleT5-R;700857]so if I'm reading this right, you've got 2 duff pumps then ??[/QUOTE] no you're not reading it right, i have 2 good pumps
[QUOTE=AAnickmac;700839]these are really common as a breakdown. i thought it was a green relay behind radio area. but may be blue in colour.[/QUOTE] The fuel pump relay is also the ignition relay. If my memory is right the fuel pump side of the relay comes in first then the ignition side comes in and it is behind the radio. So if the fuel pump side fails then the ignition will not come in.
[QUOTE=T5frankie;700859]no you're not reading it right, i have 2 good pumps[/QUOTE] so why do they stop pumping when as you say "[COLOR=#333333]i ran a live straight from the battery to the pump worked but still didnt stay running" [/COLOR][COLOR=#333333]or do you mean the pump continued to run but the ignition cut [/COLOR][COLOR=#333333][/COLOR]
[QUOTE=MoleT5-R;700851]stirrer.......lol[/QUOTE] me? never ;)
[QUOTE=MoleT5-R;700864]so why do they stop pumping when as you say "[COLOR=#333333]i ran a live straight from the battery to the pump worked but still didnt stay running" [/COLOR][COLOR=#333333]or do you mean the pump continued to run but the ignition cut [/COLOR][COLOR=#333333][/COLOR][/QUOTE] I didn't say they stopped pumping just my car won't run for more than a second
[QUOTE=T5frankie;700917]I didn't say they stopped pumping just my car won't run for more than a second[/QUOTE] but you didn't say that when the car cut out, the pump was still working, but all that aside it looks like an ignition fault afaik
Ignition and fuel is controlled by two relays, fuel pump (white) and radio suppression relay.. Sounds like ignition problem..
[QUOTE=jks;700974]Ignition and fuel is controlled by two relays, fuel pump (white) and radio suppression relay.. Sounds like ignition problem..[/QUOTE] NO. one relay controls the fuel pump and ignition. I should no.............. I've had a 740 turbo intercooler which had a starting problem. One minute I had fuel but no spark or no fuel and a spark. Got a new relay and had years of trouble free motoring.
[QUOTE=oblark;700976]NO. one relay controls the fuel pump and ignition. I should no.............. I've had a 740 turbo intercooler which had a starting problem. One minute I had fuel but no spark or no fuel and a spark. Got a new relay and had years of trouble free motoring.[/QUOTE] YES. Lol Radio suppression relay is connected to fueling. http://www.davebarton.com/volvorelays.html
[QUOTE=jks;700978]YES. Lol Radio suppression relay is connected to fueling. http://www.davebarton.com/volvorelays.html[/QUOTE] where is the radio supression relay? bearing in mind the 940 is different
http://www.volvoclub.org.uk/faq/EngineFuelinjection.html#Radio_Suppression_Relay The radio suppression relay is also fuel injection relay.
Surely you cant miss a relay that controls the fuel pump, ignition, fuel injection and the radio........... it must be the size of shoe box.
[QUOTE=oblark;701032]Surely you cant miss a relay that controls the fuel pump, ignition, fuel injection and the radio........... it must be the size of shoe box.[/QUOTE] no just a normal size,
Dont know if it helps but The cooling fan relay is same part number so could just swap that in and see if it works. know the relay is at fault then.
Frankie , just trying to help again as others think i am a complete arsole........but i owned 4x 740`s and on 3 of them the motor misfired and also stopped while driving and it was traced to the earthing of this Amplifier Ignition Unit or Power Unit on the inside of the right hand wing looking at the car from the front. Undo the bolts holding it and scrape the rust off the body and re bolt up and it should if the problem be ok..........it is a very common thing with 740`s as the 940 is different....it is just the Earthing of the unit! Hope it helps you! ..................................
[QUOTE=960kg;701137]Frankie , just trying to help again as others think i am a complete arsole........but i owned 4x 740`s and on 3 of them the motor misfired and also stopped while driving and it was traced to the earthing of this Amplifier Ignition Unit or Power Unit on the inside of the right hand wing looking at the car from the front. Undo the bolts holding it and scrape the rust off the body and re bolt up and it should if the problem be ok..........it is a very common thing with 740`s as the 940 is different....it is just the Earthing of the unit! Hope it helps you! ..................................[/QUOTE] thanks for the help but its running again now, i took the fuel pump relay out, put it in again and it works now lol WTF?? i'm not complaining though lol car is now ready for its retest
Despite all sarcasm everywhere i am glad you are sorted........but do check the rusted bolts on this power unit as it does cause problems on the 740
[QUOTE=960kg;701141]Despite all sarcasm everywhere i am glad you are sorted........but do check the rusted bolts on this power unit as it does cause problems on the 740[/QUOTE] every nut and bolt has rust on it, when i tried to replace the intank fuel pump, all the jubilee clips had no heads on they were that rusted