V70 D5 sudden power power loss

[Bernard333]

125k miles and now having problems , replaced failed diesel lift pump with a Denso pump from a 2000 Toyota ( its fits exactly into the Volvo/ Bosch plastic brackets and filter , all the pipes were able to fit and measured pressure is 2 Bar same as original Volvo but cost £10 instead of the £250 quoted by Volvo ). Car is still having problems , when tank gets less than 70%full car will not start and ' Urgent Engine System Service' comes on . Pipes in fuel tank are all in correct place and reaching the bottom of the tank. Second problem is that when trying to accelerate hard the same ' Urgent Engine System Service ' message comes up and loss of power ensues which can be restored by turning off the ignition and back on again . Under normal driving conditions everything seems ok and fuel consumption is fine at 50mpg +. Local mechanic used engine diagnostic on the engine and says there is no problem from the engine forwards , the engine mounted low and high pressure pumps are ok and the injection system working correctly as evidenced by everything being ok , any ideas what could be wrong ?

[John_C]

Did your mechanic tell you what the fault codes were when you had the diagnostic done as that's a good place to start?

If you've not got the fault codes then as a starting point you'll need to get them read again so you know what the car thinks is wrong with it.

Cheers,
John

[Bernard333]

No , I should have asked but also I had flattened the battery and the in car display had reset itself so dont know if this affects the fault code memory also ? I will be taking the car back to same mechanic ( local Volvo dealer actually recommended him and hes got a great reputation locally here in Ireland ) , I have lived with the power problem for about 25k miles and every advice I could get pointed to the lift pump which did eventually fail ,have downloaded scantool.net and am planning to buy an obd11 serial connector from ebay so I can see whats wrong for myself but just a bit concerned that I might do something that might bugger up the car completely .

[shimon340]

I didnt think the Bosch system would work successively with a Denso pump fitted. Control system etc would be different leading to interesting(!) pressure control results!

[Bernard333]

the Volvo/Bosch pump that was removed has just two wires to the motor and the Denso pump looked exactly the same even down to the electrical connector in the Volvo mounting assembly fitting into the Denso pump with no mods . The replacing of the pump did immediately resolve the starting problem and I have covered 4000 miles this past 3 weeks ( learning that the fuel tank needs to be 70% full was an expensive one , broke down near St Quentin in France and they charged 164 Euro to bring 25L of Diesel to me , I suppose I was lucky that the breakdown man spoke good english as I could see he was having difficulty believing me that just adding deisel would get it started again especially as he checked himself that the tank was already showing three quarters full - he was shaking his head in disbelief). I cant see that there can be any pressure control for the fuel tank lift pump as its either receiving power or not as its just a 12V pump with a constant 2bar pressure output feeding the low pressure section of the engine mounted pump please correct me if I am wrong , or is there some voltage control applied to the motor to regulate the pressure ?

[shimon340]

ah.. the fuel tank pump.

Interesting that they are so similar. So long as the output at a given voltage is the same then I suppose the denso one could work. The fact the tank needs to be over 70% is interesting. Are there no fault codes registered?

there are a number of reasons why high pressure diesels can cut out, one can be if the high pressure pump pressure regulator fails and the output pressure rises too far, the common rail will note the over pressurisation and release all the pressure from the rail - via a kind of safety valve. This results in the engine cutting out. this should log a fault code however.

alternatively, the low pressure feed pressure is too low. would also trip a fault code though but might explain the 70% issue. below 70% full the output pressure from the pump is too low. high pressure pump maintains rail pressure by measuring input and fuel return levels.

are the symptoms the same now as when the original bosch pump was replaced with the denso one?

alternatively, there is a pressure regulator on the common rail, this could be at fault too. or, if one injector intermittantly returns too much fuel, the HPP responds by cutting the pressure to the rail. This then means the injectors are leaned out which can result in stalling.

where abouts in the uk are you? I have a friend who works for Bosch and who is also a volvo and D5 expert.

[Djole]

Originally Posted by John_C

Did your mechanic tell you what the fault codes were when you had the diagnostic done as that's a good place to start?

If you've not got the fault codes then as a starting point you'll need to get them read again so you know what the car thinks is wrong with it.

Cheers,
John

I've had the same problem but according to the diagnostic tests there is nothing wrong the car. The mechanic took it for a spin and experienced the loss of power I had . I've had to leave my car (V70 D5 Sport - 2007)overnight and he tells me trying to find out what is wrong is like looking for a needle in a haystack ! Can anyone please help??

[portacabin1]

Originally Posted by Bernard333

125k miles and now having problems , replaced failed diesel lift pump with a Denso pump from a 2000 Toyota ( its fits exactly into the Volvo/ Bosch plastic brackets and filter , all the pipes were able to fit and measured pressure is 2 Bar same as original Volvo but cost £10 instead of the £250 quoted by Volvo ). Car is still having problems , when tank gets less than 70%full car will not start and ' Urgent Engine System Service' comes on . Pipes in fuel tank are all in correct place and reaching the bottom of the tank. Second problem is that when trying to accelerate hard the same ' Urgent Engine System Service ' message comes up and loss of power ensues which can be restored by turning off the ignition and back on again . Under normal driving conditions everything seems ok and fuel consumption is fine at 50mpg +. Local mechanic used engine diagnostic on the engine and says there is no problem from the engine forwards , the engine mounted low and high pressure pumps are ok and the injection system working correctly as evidenced by everything being ok , any ideas what could be wrong ?

Hello bernard 333,
I have a v70d5 that used to cut out and would then have to be started by turning the key not of a bump start, the warning lightes came on ect, this would happen every 10 to 15 miles. After getting very depressed i found from this site that the main dealer can reprogram your ecu. after 20 mins mt local volvo agent in coventry charged me just over £60.00 and i have done hundreds of miles since, this might sort your problem. All the best

[Bernard333]

thanks for the advice portacabin , sounds like a possible solution , my main problem is getting to stay in one place long enough for a main dealer to look at the car , I am mainly in donegal ireland and the main volvo dealer has so much work on they cant even give me a date for looking at it . Have just spoken with Howard at Horwich motors as advised by Shimon and am hoping to get the car into Manchester within the next few weeks . Howard advised that problem with the tank needing to be 70% full could be because the V70 tank is split into 2 with a pipe connecting the two halves and there could be some issue with air in the pipe or it not having been placed correctly within the tank . I am going with this theory for now and will check it out this weekend if it stays dry but I am fairly certain the car has multiple problems and this may not be the answer to the power problem so will still plan to take it to Horwich motors . I can still drive the car and knowing what the limitations are I can manage to keep on going but as you can imagine its not ideal being unable to put your foot down when needed and also having to always ensure the fuel tank is full .