Fuel pressure problems

Hi been busy just having another look at this Td5 and just check fuel pressure and only reading 1.2 bar its had a replacement intank pump still only got 1.2 bar did pressure check through temperature sensor any ideas

I have also put the gauge on the hp supply to the engine and only getting 1.2 bar

Wilf g said:

Hi been busy just having another look at this Td5 and just check fuel pressure and only reading 1.2 bar its had a replacement intank pump still only got 1.2 bar did pressure check through temperature sensor any ideas

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Then if you are sure that your gauge is accurate and the pump is not fubar do this test Check Td5 fuel pump HP and measure voltage in the pump's plug cos it's possible to be a voltage drop, if the mV reading across F10 is good means that the pump works but the pressure supply pipe is clogged or something

Hi Reading at fuse 11.3 so not good
I have run the battery low so on charge again. but I put a 12v supply and earth to the pump and still only low pressure 1.8 bar

Hi Reading at fuse 11.3 so not good
I have run the battery low so on charge again. but I put a 12v supply and earth to the pump and still only low pressure 1.8 bar

is the pump 100% good and well connected to the pipes, i've seen cases when the pipes at the pump were mixed up, the colours of clips should be white-green-blue-black(from left to right)

Yeah pipes are on in right order and pump is new after market

Wilf g said:

pump is new after market

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and are you sure it was not DOA? `as long as there's not around 23mV across F10 it can't deliver HP, that was verified not once

So if I am getting this if the hp was working the reading would be 23mv across fuse so suspect pump Doa

As long as you get 12V in the pump's connector while it's runing and not around 23mV across F10 that pump is fubar

OK I'll double check in the morning when battery fully charged and get back

Hi just checked with charged battery getting 12.6 mv across fuse .battery 12.46v across terminals,only getting 11.13at pump plug when pump running ,12.32 when not running

You should try with a 100% good pump cos it's in a grey zone, 12.6mV is too low for HP but a bit high for LP, you can't rely on unbranded cheap aftermarkets

sierrafery said:

You should try with a 100% good pump cos it's in a grey zone, 12.6mV is too low for HP but a bit high for LP, you can't rely on unbranded cheap aftermarkets

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Cheers have just checked again and got 13mv 11.7v pump running 1.8 bar.

Hi still not got fuel pressure I have got 15.4 mv across f10 and 11.45v at pump when pump running but still only getting 1.2 bar at temp sensor any ideas this is the 3rd pump tried

Update up and running loads of smoke at first starting now cleared turned of and restarted under own power no leads,I'll try it again in the morning fingers crossed it will start.
Many thank for all the help cheers wilf

Daft question, but doesnt the fuel pressure regulator keep 4 bar of pressure in the head, before it opens, and returns the fuel to the tank. If the FPR is knackered, ie partially open, it will dump most of the pressure back into the tank.... or have I got it wrong...

I only had 1.2 bar with connected direct to high pressure pipe