Freelander 1 TD4 warm start problems

Nodge68 said:

It still sounds like the pressure regulator O rings to me. If the regulator O ring splits or doesn't seal tight, then the pumped fuel simply flows back to the tank via the return line. This gives the impression of no or very low rail pressure. It's definitely worthwhile changing the regulator O rings as they cost about £5 and take an hour or so to fit.

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Thanks Nodge, took my old pump apart and found the green o ring was ok but the white support collar had seen better days. Picking up the a new collar and o ring from the Bosch agent tomorrow, he said they would be pennies. If that fixes the problem I will not be a happy bunny.

Edit to add:

Do you take the starter off for easier access, I'm gonna take the inlet manifold etc off again as it will make my life easier, but wasn't sure about the starter

No need to remove the starter, as long as the Torx screws come out OK.

Nodge68 said:

No need to remove the starter, as long as the Torx screws come out OK.

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Cheers mate, got it out and the seals look fine, bought the o ring, collar and gasket today just in case and will replace them anyway. Had the LP fuel rail off and switched the ignition on, fuel shot out about 10 ft in the air so getting fuel to the HP pump. Tried easy start but it runs an then dies still showing no HP fuel pressure. I'm thinking maybe the HP rail pressure switch is faulty, anyway of checking it?

If its just a pressure switch, put a multimeter (on resistance) across the contacts, turn on the HP pump and it should switch over.

ianda12 said:

If its just a pressure switch, put a multimeter (on resistance) across the contacts, turn on the HP pump and it should switch over.

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The rail sensor is a variable output device, not a switch. There are 2 such devices in the TD4 fuel system. One for the low pressure rail and one for the high pressure rail.

Would you not see a resistance change rather than an open/closed circuit change, or would that be to easy ?

ianda12 said:

Would you not see a resistance change rather than an open/closed circuit change, or would that be to easy ?

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You can measure the signal wire voltage at the ECU. You can't measure resistance at the sensor because it's not a resistive device. It's an active sensor with 3 wires. It is fed with +5 volts, a ground and outputs a variable voltage on the signal wire in relation to the pressure applied to the sensor.

Bit of an update. I've replaced the seals on my old fuel pressure regulator and refitted it. I've also fitted new rubber hoses coming of the HP pump, I had to cut the old ones off and used straight fuel pipe, this didn't like being bent at 90 degrees so used jubilee clips on the bend to stop it collapsing, it looks like one may have collapsed completely, this may explain why the LP was good but I was seeing no HP.

As a side note Land Rover won't sell the rubber hoses in their own you have to be the whole LP fuel line assembly, nearly 200 quid, as luck would have it Rimmer bros had the whole assembly for £27 +vat, turned up yesterday and it's genuine BMW! I've taken the rubber pipes off so will be able to sell the metal assembly hopefully.

Off to get another HP rail sensor, fingers crossed it starts later today.

Right it's running thank xxxx. Not sure what the issue was as this morning I swapped the solenoid from my old pump (with new seals) replaced the two rubber fuel pipes on the pump with genuine ones and replaced the HP rail sensor. Hopefully that's ended it!

S1monm said:

Right it's running thank xxxx. Not sure what the issue was as this morning I swapped the solenoid from my old pump (with new seals) replaced the two rubber fuel pipes on the pump with genuine ones and replaced the HP rail sensor. Hopefully that's ended it!

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It was probably the HP solenoid or its O rings. The engine will often still run with the rail sensor faulty, although badly.
Glad you're sorted now.

Nodge68 said:

It was probably the HP solenoid or its O rings. The engine will often still run with the rail sensor faulty, although badly.
Glad you're sorted now.

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Thanks for your help mate

I've got the same problem with a 2003 td4. Starts from cold but won't start without easy start once warm. Mine smokes though when you rev it. White smoke which smells of diesel. It's as if it's overfuelling or not atomising the diesel and lumpy around 2000 rpm. Also sometimes the MIL comes on but never registers a fault code. Fed up of changing parts on it. Have read the posts on here and spent a fortune. LP pump and filter, two injectors refurbished, cam sensor, fuel rail sensor and harness, all to no avail. I'd be grateful if someone could suggest some possible solutions before I completely loose my rag and put a match to it.

J111HJH said:

lumpy around 2000 rpm

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This is ‘normal’ if not under load.

J111HJH said:

MIL comes on but never registers a fault code

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You might need a better code reader. A common rail engine needs proper diagnostics, or you’ll be changing parts forever.

J111HJH said:

two injectors refurbished,

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Refurbish the other two - one or both could be dropping rail pressure and preventing starting, Consider a leakback test when warm.

Also, change the HP regulator O-rings.

Thanks for recommendations. Leak back tests suggested refurb for two injectors. Can you recommend a code reader? I've got a cheap obd2 reader and a Bluetooth elm327 reader. Will try HP regulator O rings. Regards. Julian

J111HJH said:

Thanks for recommendations. Leak back tests suggested refurb for two injectors. Can you recommend a code reader? I've got a cheap obd2 reader and a Bluetooth elm327 reader. Will try HP regulator O rings. Regards. Julian

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ICarsoft i930 and Pscan will do yours. OBD2 and elm327 ones are hopeless.

Thank you for your help. I'll keep you informed.

J111HJH said:

Thank you for your help. I'll keep you informed.

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Did you fix it?

Any luck with this fault?
I got the same - starts perfect when cold - but when hot it starts then stalls. Sometimes it starts 2nd crank and sometimes it takes 10 times. But when it starts it drives and doesnt stop.
Thinking about replacing the High Pressure Sensor O ring when reading here..

Sorry for late reply. Haven't logged on for some time. Advice supplied by guineafowl was spot on. Replaced high pressure pump and it was like a new vehicle!