Engine turning over but refusing to start

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KennyW
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Re: Engine turning over but refusing to start

Post by KennyW »

Thanks Richard and Pete for your replies,

I was advised not to turn the engine over too much because it will eventually knacker the HP fuel pump.

The only figures I can get were recorded at the time of the fault and the car was stationary.

I will look at the wiring relating to the crankshaft and camshaft sensors.

It is strange the problems with starting may relate to the crankshaft sensor or associated wiring.

Going to have a look at it today.

Will get back with another update.

Kenny
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KennyW
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Re: Engine turning over but refusing to start

Post by KennyW »

Quick update, one of the wires on the crankshaft plug plastic sheath is broken through to the wire unknown of completely severed.

Can this be part of the problem ?

Also can someone fix the weather as it's getting colder and is going for my back.

Thoughts please on all of the above

Kenny
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Re: Engine turning over but refusing to start

Post by wheeler »

If any of the wires to the crank sensor are broken the car will not start. If it has rubbed through to the copper it may be corroded & have a high restance which would likely cause a non start situation. A quick check on live data will show if there is engine RPM on crank.
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Re: Engine turning over but refusing to start

Post by aerodynamica »

I hope this wire is all that's wrong Kenny!
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Re: Engine turning over but refusing to start

Post by Sloppysod »

KennyW wrote:
13 Jan 2022, 17:05
Also can someone fix the weather as it's getting colder and is going for my back.
Kenny
Hi Kenny, best I can do. Not too hot.....
Good luck, hope it is a simiple as a corroded wire, and it is easy to get to.
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KennyW
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Re: Engine turning over but refusing to start

Post by KennyW »

Thanks for the replies and encouragement special thanks to Stu for the weather forecast

Will get back to you with and update or result

Final question though are crankshaft sensor plugs the same on all marks of the C5 ie 2.0 Hdi and other associated brands with same engine.

Thinking of splicing in another plug on to loom.

Kenny
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Re: Engine turning over but refusing to start

Post by wheeler »

No, some early C5's had 2 pin inductive type sensors, yours is a 3 pin hall effect type.
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Re: Engine turning over but refusing to start

Post by KennyW »

Thanks wheeler,

Going to do the rounds at scrap yards with a sensor to get the right plug.
I've checked my old citroen freebee and the the sensor starts as 1920 7V replaced by 1920 QN (2.0 HDi).

Kenny
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Re: Engine turning over but refusing to start

Post by KennyW »

Quick update, plastic fuel pipe from tank to filter is fine so can rule that out as a problem.

But having an issue with priming pump is not able to draw diesel from tank in to filter. Hand pump does not have any leaks.

Waiting on wiring and heat shrank connectors to arrive to repair wire.

Kenny
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GiveMeABreak
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Re: Engine turning over but refusing to start

Post by GiveMeABreak »

Your fuel tank has a gauge without pump - for info Kenny. Fuel Supply Components Below:
Kenny Fuel compoenents.JPG
Key:
  • "A" Electrical links
  • "B" Low pressure fuel circuit
  • "C" High pressure fuel circuit
  • "D" Heated low pressure fuel circuit
ReferenceDesignationElectrical diagram correspondence
(1)Fuel high pressure common injection rail-
(2)Engine ECU1320
(3)high pressure fuel pump1208
(4)Fuel cooler-
(5)Fuel tank-
(6)Manual fuel primer pump-
(7)Diesel injector (1) ; (2) ; (3) ; (4)(1331, 1332, 1333, 1334)
(8)Fuel filter-
"a"Fuel high pressure sensor1321
aerodynamica
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Re: Engine turning over but refusing to start

Post by aerodynamica »

Is the pump driven off the camshaft? Unlike my old school Xantia with the pump driven by the cambelt
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GiveMeABreak
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Re: Engine turning over but refusing to start

Post by GiveMeABreak »

No, on these, they use a transfer pump which is built into the High Pressure Fuel pump which is all electronically controlled. It is shown as 'g' below.
Kenny HP Fuel pump.JPG
"g" Transfer pump (pre-supply).
"h" High pressure fuel outlet.
"j" Diesel temperature sensor.
"k" Fuel flow regulator.
"l" High pressure fuel pump identification plate.
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Re: Engine turning over but refusing to start

Post by RichardW »

Slight cross purposes there, Marc - Graeme was getting at the fact that the injection pump (which you have shown to include a lift pump) is driven off the flywheel end of the camshaft, rather than direct by the cambelt.

I'm sure there were a couple of instances of the camshaft breaking, but I think this was the 2.2 engine as fitted to the C-Crosser / 4007 (and one of the things that put me off buying one!).
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Re: Engine turning over but refusing to start

Post by GiveMeABreak »

...wood for the trees and all that Richard! :-D

May as well put up some more about the internals for the pump in case it helps with the case.

Transfer pump (pre-supply)

"m" rotor.
"n" Fins.
"p" High pressure pump shaft.
"q" Stator.

Role of the transfer pump:
  • To pump fuel into the fuel tank
  • To supply the fuel high pressure pump (Compresses the fuel upstream of the fuel flow regulator)
  • Lubrication and cooling of the fuel high pressure pump
The transfer pump (volumetric with 4 fins) is incorporated in the casing of the fuel high pressure pump.
A regulation valve maintains the transfer pressure at a constant value (6 bars) throughout the engine operating range by returning a proportion of the fuel to the transfer pump inlet.
Kenny Fuel compoenents C.JPG
Creating the High Pressure

The high pressure fuel pump consists of two radial pistons.
The roller pushed by the eccentric pump shaft moves transversely: The high pressure is generated in the fixed part of the fuel high pressure pump.
Kenny Fuel compoenents B.JPG

"B" Low pressure.
"C" High pressure.
"g" Transfer pump (pre-supply).
"r" Inlet valve for the compression chamber of the fuel high pressure pump.
"s" Outlet valve for the compression chamber of the fuel high pressure pump.
"t" Plunger piston.
"u" Thrust pad.
"v" Eccentric pump shaft.
"w" Roller.

Fuel high pressure creation cycle:
  • The eccentric pump shaft "v" positions the roller "w" in the low position.
  • The plunger piston "t" descends.
  • The fuel arriving from the transfer pump "g" via the fuel flow regulator is drawn in through the inlet valve "r".
  • The fuel penetrates into the body of the pumping element.
  • When the eccentric pump shaft "v" rotates, the roller "w" rises again and pushes the plunger piston "t".
  • The pressure in the body of the pumping component increases and becomes higher than the transfer pressure: The high pressure pump compression chamber inlet valve "r" closes.
  • The pressure in the body of the pumping component continues to increase and becomes higher than the pressure from the fuel high pressure common injection rail: The high pressure pump compression chamber outlet valve "s" opens.
  • The fuel is delivered to the high pressure pump compression chamber outlet valve "s".
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KennyW
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Re: Engine turning over but refusing to start

Post by KennyW »

Marc thanks for all that. I hope it’s not the pump.
I do have an authorised Delphi/ Bosch pump specialist in Fife.
But it will cost few hundreds to fix.
I am waiting on bits to vacuum test the LP side from tank to pump. Luckily I have vacuum pump which is from a motorcycle brake bleed kit, must try it on the car brakes.
Will report back later
Kenny