Yes me too. If it will tickover with priming bulb assistance then the HPFP must be working surely?
High pressure fuel pump replacement
- Thread starter stevethejoiner
- Start date
Yes me too. If it will tickover with priming bulb assistance then the HPFP must be working surely?
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This is not a high pressure pump problem. The engine management system on a common rail diesel will not even trigger the injectors unless the pressure in the fuel rail reaches a pre-determined point, so the fact it starts and runs when being primed suggests the high pressure pump is healthy. The problem is with the delivery of fuel to the high pressure pump, so will be somewhere on the low pressure side. It will be either the lift pump itself, or an air leak somewhere between the lift pump, and high pressure pump inlet.
You could confirm this by disconnecting the fuel inlet to the high pressure pump, and rigging up a clean container with clean diesel in it (cleanliness is critical) directly into the high pressure pump inlet. Hold the container above the pump so gravity does its stuff, and I bet the van starts and runs fine.
Don't disturb anything on the high pressure side at all. The unions on the pipes are single use, and if they are even slightly disturbed, the pipes need replacing. The pressure in these systems is phenomenal, and any escaping diesel could be under such pressure that it would be not only invisible, but capable of penetrating your skin and getting into your bloodstream. It is not melodramatic to state that if this happened, you wouldn't make it to casualty. Play around on the low pressure side by all means, but leave the high pressure side to the pros. And once again, cleanliness is critical on modern fuel systems.
Good luck!
You could confirm this by disconnecting the fuel inlet to the high pressure pump, and rigging up a clean container with clean diesel in it (cleanliness is critical) directly into the high pressure pump inlet. Hold the container above the pump so gravity does its stuff, and I bet the van starts and runs fine.
Don't disturb anything on the high pressure side at all. The unions on the pipes are single use, and if they are even slightly disturbed, the pipes need replacing. The pressure in these systems is phenomenal, and any escaping diesel could be under such pressure that it would be not only invisible, but capable of penetrating your skin and getting into your bloodstream. It is not melodramatic to state that if this happened, you wouldn't make it to casualty. Play around on the low pressure side by all means, but leave the high pressure side to the pros. And once again, cleanliness is critical on modern fuel systems.
Good luck!
Sorry for the delay I have been away.
Very useful reply, I shall let you know next week how I get on with what you said. Thanks again Steve.
I thought I had updated this, but obviously I didn't.
I will now in case others have engine cutting out problem.
I did have a new HP pump fitted, and all was good for a time but after a short while later the engine started cutting out again.
Quite simply, in the end, all it was, was the rubber hand fuel primer bottle. The inner one way valve/baffle had deteriorated.
Changed the primer bottle, and its been ok ever since. I never needed a new HP pump after all.
I will now in case others have engine cutting out problem.
I did have a new HP pump fitted, and all was good for a time but after a short while later the engine started cutting out again.
Quite simply, in the end, all it was, was the rubber hand fuel primer bottle. The inner one way valve/baffle had deteriorated.
Changed the primer bottle, and its been ok ever since. I never needed a new HP pump after all.
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Why?
Why because I am not a mechanic, I was getting conflicting ideas what was wrong. It's ok saying it not HP Pump for this and that, but other than the low and high pressure pump no one came up with another fault or said try changing priming bottle. Mechanics had investigated what else it could be. I had 3 experts including main Renault dealer say HP Pump so paid to change it.
An interesting if expensive outcome......sure I've had primer bulbs fail before, but once the engine got going it remained so until the next start up.
I've had similar issues with an Iveco truck.....sometimes good for days, sometimes conked every 10 mins. I baled out from that one as I didn't want to be responsible for a £1000 gamble. As it happens, Iveco fitted a new HP pump and that did sort it - but it was constantly flagging up an EGR fault code, even with that renewed. I sympathise with any mechanic who doesn't get the diagnostics right first time!
Let's hope that's the end of your problems, Steve!
John
I've had similar issues with an Iveco truck.....sometimes good for days, sometimes conked every 10 mins. I baled out from that one as I didn't want to be responsible for a £1000 gamble. As it happens, Iveco fitted a new HP pump and that did sort it - but it was constantly flagging up an EGR fault code, even with that renewed. I sympathise with any mechanic who doesn't get the diagnostics right first time!
Let's hope that's the end of your problems, Steve!
John
