- You are currently viewing DISCO3.CO.UK as a guest - Register to take part or Log In
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8166
  
|
What is the history of the engine? - You say it's new has it ever run? - You say it fired but didn't run, that suggests the valve timing is ok.
If you've got fuel (Mikey says it should start with 140KPa pressure) and you've got compression the only thing left is timing, it could fire if the injector timing was out but will not run, check/change the crank sensor. It can when others can't,
It will when others won't,
It goes where others don't.
|
 4th Mar 2014 9:22 pm |
|
|
fast1cars
Member Since: 27 Dec 2013
Location: bury st edmunds
Posts: 72
  
|
so here we go.
brand new engine from landrover.
brand new turbo-turbo technics
2 brand new egrs
brand new starter
new battery
brand new cam sensor
the code reader just comes up fuel pressure stuck low.P0191error cheers John
Classic rangerover 3.5 V8 -sold now
Classic rangerover -6.2 gmc deisel sold now
Classic rangerover 3.9v8 sold now
P38 4.0 v8 sold now
Disco 1 3.9v8 sold now
Discovery 2 TD5 just sold
sierra cosworth with 498BHP fastest car I have ever owned-now sold
megabusa currently lots of fun
current Disco 3- broken at the moment
|
| 4th Mar 2014 9:25 pm |
|
|
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20794
 
|
M3DPO wrote:It would not start on 140KPA=20psi 
You are correct. 14,000kPa is required 
Does the pressure drop away to nothing when the engine has stopped cranking, or does it stay at 140? My D3 Build Thread
TDV8 Retrofit Build Thread
|
| 4th Mar 2014 9:42 pm |
|
|
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8166
|
You also need to double check if it is MPa or KPa
Thanks Mikey. It can when others can't,
It will when others won't,
It goes where others don't.
|
| 4th Mar 2014 10:02 pm |
|
|
Valhalla
Member Since: 23 Oct 2011
Location: Isle of Skye
Posts: 124
|
Or, more likely, whether your scantool is reading out BAR, in which case 140BAR is quite plausible to see in a fuel rail, but too low to reliably start (you are off the bottom of the injector mapping).
So as above, you need to confirm what units you are reading.
1BAR = 100kPa = 0.1MPa
Normal idle rail pressure for 800rpm would be circa 265BAR. To confirm that the injectors are even being controlled open during cranking, you need to watch and smell the exhaust for diesel fuel vapour or cold (blue) smoke. If you are cranking the thing over, and the workshop hasn't been filled with accrid emissions, then the injectors are not opening = insufficient rail pressure is being generated during cranking to switch them on (if they are switched-on prematurely, the engine will flood with low spray pressure fuel). That low pressure, assuming it goes to zero inbetween starts, and goes up a bit during crank, would suggest that you have a rail pressure sensor feedback (albeit it might be broken) so the wiring is good, but the HPFP is not generating enough pressure.
|
| 5th Mar 2014 1:37 am |
|
|
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8166
|
FUEL RAIL PRESSURE CONTROL VALVE
The fuel rail pressure control valve is incorporated into the high pressure fuel pump. The control valve regulates the fuel pressure within the fuel rail and is controlled by the ECM. The control valve is a PWM controlled solenoid valve.
When the solenoid is de-energised, an internal spring holds an internal valve closed. At fuel pressure of 100 bar (1450 lbf/in²) or higher, the force of the spring is overcome, opening the valve and allowing fuel pressure to decay into the fuel return pipe. When the pressure in the fuel rail decays to approximately 100 bar (1450 lbf/in²) or less, the spring force overcomes the fuel pressure and closes the valve. When the ECM energises the solenoid, the valve is closed allowing the fuel pressure to build. The pressure in the fuel rail in this condition can reach approximately 1300 bar (18854 lbf/in²).
The ECM controls the fuel rail pressure by operating the control valve solenoid using a PWM signal. By varying the duty cycle of the PWM signal, the ECM can accurately control the fuel rail pressure and hence the pressure delivered to the injectors according to engine load. This is achieved by the control valve allowing a greater or lesser volume of fuel to pass from the high pressure side of the pump to the un-pressurised fuel return line, regulating the pressure on the high pressure side.
The fuel rail pressure control valve receives a PWM signal from the ECM of between 0 and 12V. The ECM controls the operation of the control valve using the following information to determine the required fuel pressure:
ô€º Fuel rail pressure
ô€º Engine load
ô€º Accelerator pedal position
ô€º Engine temperature
ô€º Engine speed.
In the event of a total failure of the fuel rail pressure control valve, the engine will not start. It can when others can't,
It will when others won't,
It goes where others don't.
|
| 5th Mar 2014 8:33 am |
|
|
fast1cars
Member Since: 27 Dec 2013
Location: bury st edmunds
Posts: 72
|
Disco_Mikey wrote:M3DPO wrote:It would not start on 140KPA=20psi
You are correct. 14,000kPa is required
Does the pressure drop away to nothing when the engine has stopped cranking, or does it stay at 140?
hi the pressure drops away after cranking.Do you have a mob number so i can ring you. cheers John
Classic rangerover 3.5 V8 -sold now
Classic rangerover -6.2 gmc deisel sold now
Classic rangerover 3.9v8 sold now
P38 4.0 v8 sold now
Disco 1 3.9v8 sold now
Discovery 2 TD5 just sold
sierra cosworth with 498BHP fastest car I have ever owned-now sold
megabusa currently lots of fun
current Disco 3- broken at the moment
|
| 5th Mar 2014 12:17 pm |
|
|
fast1cars
Member Since: 27 Dec 2013
Location: bury st edmunds
Posts: 72
|
M3DPO wrote:FUEL RAIL PRESSURE CONTROL VALVE
The fuel rail pressure control valve is incorporated into the high pressure fuel pump. The control valve regulates the fuel pressure within the fuel rail and is controlled by the ECM. The control valve is a PWM controlled solenoid valve.
When the solenoid is de-energised, an internal spring holds an internal valve closed. At fuel pressure of 100 bar (1450 lbf/in²) or higher, the force of the spring is overcome, opening the valve and allowing fuel pressure to decay into the fuel return pipe. When the pressure in the fuel rail decays to approximately 100 bar (1450 lbf/in²) or less, the spring force overcomes the fuel pressure and closes the valve. When the ECM energises the solenoid, the valve is closed allowing the fuel pressure to build. The pressure in the fuel rail in this condition can reach approximately 1300 bar (18854 lbf/in²).
The ECM controls the fuel rail pressure by operating the control valve solenoid using a PWM signal. By varying the duty cycle of the PWM signal, the ECM can accurately control the fuel rail pressure and hence the pressure delivered to the injectors according to engine load. This is achieved by the control valve allowing a greater or lesser volume of fuel to pass from the high pressure side of the pump to the un-pressurised fuel return line, regulating the pressure on the high pressure side.
The fuel rail pressure control valve receives a PWM signal from the ECM of between 0 and 12V. The ECM controls the operation of the control valve using the following information to determine the required fuel pressure:
ô€º Fuel rail pressure
ô€º Engine load
ô€º Accelerator pedal position
ô€º Engine temperature
ô€º Engine speed.
In the event of a total failure of the fuel rail pressure control valve, the engine will not start.
Thanks for this information after some fault finding today i found that the low pressure tank pump only have 2 psi of pressure and i understand these need 5 - 7 psi would you agree on this cheers John
Classic rangerover 3.5 V8 -sold now
Classic rangerover -6.2 gmc deisel sold now
Classic rangerover 3.9v8 sold now
P38 4.0 v8 sold now
Disco 1 3.9v8 sold now
Discovery 2 TD5 just sold
sierra cosworth with 498BHP fastest car I have ever owned-now sold
megabusa currently lots of fun
current Disco 3- broken at the moment
|
| 5th Mar 2014 4:40 pm |
|
|
Valhalla
Member Since: 23 Oct 2011
Location: Isle of Skye
Posts: 124
|
Yes, I would agree that you low pressure fuel supply from the tank is way too low. It is less critical on the SVDO HPFP than, say, a Bosch CR1, but nonetheless, it isn't giving you the best chance of starting this engine. You should be seeing around 0.4BAR feed pressure from the tank, measured at the back of the HPFP. If the engine was already started and running, then it wouldn't matter so much if the feed pressure was abit low; it's the return line back-pressure that matters most on these.
If your rail pressure is decaying on cranking, you have a low pressure supply issue for sure. The information quoted above, regarding the PCV operation, is only applicable once an engine speed threshold has been exceeded; the PWM signal into the solenoid is open-loop at cranking-speed. If memory serves me correctly, the threshold is around 400rpm, and you will be cranking at circa 130rpm. In a healthy fuel system, the open-loop control is sufficient to build enough pressure in the rail to enable a closed-loop control to take over seamlessly for the tail end of the start.
|
| 5th Mar 2014 5:03 pm |
|
|
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8166
|
fast1cars wrote:
Thanks for this information after some fault finding today i found that the low pressure tank pump only have 2 psi of pressure and i understand these need 5 - 7 psi would you agree on this
Yes as said above 0.4/0.5 bar is best particularly on first start up, equally important IMO is flow rate, if you have a poor flow you are more likely to have low pressure, try a different fuel filter for starters, another factor on first time start is battery power/output, if the battery drops below 9v the engine is not only turning slower the injectors are programed to inject less fuel, this is an anti-emission feature. The chances of the battery dropping this low is much greater with a new tight engine.
Put an old tyre pump hose onto the Schrader valve at the back of the engine and make sure you have a full bore flow coming out, couple an extra fully charged battery with good jump leads to the existing battery to help turn the engine over at maximum speed, switch the engine on and wait for the pre-heat light to go out, turn the engine off and back on again let the pre-heat light go out and then crank.
Good Luck.
As a very last resort, if all the above has been done and it is a manual and in a convenient situation give it a tow, 5 gear at 20 mph. It can when others can't,
It will when others won't,
It goes where others don't.
Last edited by M3DPO on 5th Mar 2014 9:22 pm. Edited 1 time in total
|
| 5th Mar 2014 6:04 pm |
|
|
fast1cars
Member Since: 27 Dec 2013
Location: bury st edmunds
Posts: 72
|
Many thanks for all your help and evrybody who has had an input into this enquiry.  cheers John
Classic rangerover 3.5 V8 -sold now
Classic rangerover -6.2 gmc deisel sold now
Classic rangerover 3.9v8 sold now
P38 4.0 v8 sold now
Disco 1 3.9v8 sold now
Discovery 2 TD5 just sold
sierra cosworth with 498BHP fastest car I have ever owned-now sold
megabusa currently lots of fun
current Disco 3- broken at the moment
|
| 5th Mar 2014 7:26 pm |
|
|
waterbuoy
Member Since: 26 Oct 2013
Location: Argyll
Posts: 2893
|
I'm glad you guys seem to know what you are talking about! Currently 2009 Disco 3 SE, 2013 MY D4 HSE and 2016 D4 SE
Previously:
TD5 Defender 110 CSW (230k miles)
300TDi Disco 1 (289k)
4 RR Classics (300-350k each, 2 manual, 2 auto)
110 V8 CSW (220k)
S3 109 hi cap pickup (ex RN)
S2A 88 Safari SW with lpg conversion (bloody lethal)
|
| 5th Mar 2014 8:20 pm |
|
|
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8166
|
Seem? - what do you mean seem 
Some of us go back to the days of fitting anything from a 5.5ltr straight 6 lorry engine to a 4.4 ltr Perkins tractor engine in Range Rovers, why?- because there was nothing else available.
You youngsters don't know how lucky you are to have the joys of the TDV6, Land Rover experimented and tried to build a V6 diesel engine for 30 years and still failed until Jaguar came along.  It can when others can't,
It will when others won't,
It goes where others don't.
Last edited by M3DPO on 6th Mar 2014 8:56 am. Edited 1 time in total
|
| 5th Mar 2014 9:40 pm |
|
|
|
|
waterbuoy
Member Since: 26 Oct 2013
Location: Argyll
Posts: 2893
|
Don't worry M3DPO, I've done my fair share of re-engining (mainly boats with 3-6 cylinder Kubota based engines, but also varioius LRs) - last summer had to deal with two engines which were both hydrauliced (spelling?) and got them running again within the same day
I was merely commenting on how technical the post ahd got, and was impressed that 4 of you are managing to work together effectively via the www
Oh - and I'm no youngster! Started with a series 2A almost 30 years ago  Currently 2009 Disco 3 SE, 2013 MY D4 HSE and 2016 D4 SE
Previously:
TD5 Defender 110 CSW (230k miles)
300TDi Disco 1 (289k)
4 RR Classics (300-350k each, 2 manual, 2 auto)
110 V8 CSW (220k)
S3 109 hi cap pickup (ex RN)
S2A 88 Safari SW with lpg conversion (bloody lethal)
|
| 5th Mar 2014 10:20 pm |
|
|
|
Posting Rules
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
|
DISCO3.CO.UK Copyright © 2004-2024 Futuranet Ltd & Martin Lewis
|
|
