CDI non starter. Advice needed

markcollett · 11th June 2021, 11:35

Hello, this is my first post in a long time. I have been trying to start my 124000 mile, 2004 CDI tourer after a lay off of about a year. It was running fine before that but now won’t start. I have checked the following items: ECU for water contamination - frequently rodded through and no water marks on cabin filter and ECU looks as shined as when it left the factory. I have checked in tank and under bonnet pumps and both make a quiet hum and produce a healthy flow from the under bonnet filter. I have tried easy start and it will fire for a second or so then stop, during this I can see the Rev counter moving so I don’t think it’s the crank sensor. I have also tested the cam sensor and even though it passed test I have replaced it with new anyway. I have carried out the electrical tests for the high pressure fuel system and I get 3.97 volts on the fuel filter sensor which would suggest the two pumps are delivering good pressure. This brings me to where I think the problem lies ... I have checked the pin out voltage on the fuel rail sensor. I get 0.5 volts as expected with key at position 2 but when cranking, the voltage does not rise above 0.8 volts which would seem to indicate low rail pressure. I did a leak back test on the injectors which didn’t show any leakage from the injector bleed offs and the fact that it ran perfectly well less than a year ago suggests that it’s not an injector leak back issue. I have also changed the seal on the high pressure pump regulator (the one behind the starter motor), the old seal was intact but I changed it anyway. One thing I noticed when changing it was that there is a flexible seal and a plastic backing washer, the backing washer appeared to be cut through like a piston ring. I guess that’s so that it can be fitted over the shaft or could it be broken and that could be an issue causing leakage? My question would be where else could I look to find a cause of the low pressure in the fuel rail? One last thing, I am in south east London and nowhere near a T4 session and the car is SORN and totally immobile. Any advice on my problem would be much appreciated. Best Regards, Mark

dave lincs · 11th June 2021, 12:00

Does the oil pressure light work on the dash?

COLVERT · 11th June 2021, 14:31

You seem to have done a thorough check of just about everything that might make it a non starter.---

You didn't mention the battery or its state of charge.

If there is too great a voltage drop caused by the starter motor the ECU will sulk and not come out to play.---

If you have jump leads and access to another charged battery then the extra current available might make a world of difference when trying to start the engine.--

11th June 2021, 11:35	#1
markcollett Newbie rover 75 connoisseur 1.8t Join Date: Jul 2014 Location: Bexley Posts: 8 Thanks: 0 Thanked 0 Times in 0 Posts	CDI non starter. Advice needed Hello, this is my first post in a long time. I have been trying to start my 124000 mile, 2004 CDI tourer after a lay off of about a year. It was running fine before that but now won’t start. I have checked the following items: ECU for water contamination - frequently rodded through and no water marks on cabin filter and ECU looks as shined as when it left the factory. I have checked in tank and under bonnet pumps and both make a quiet hum and produce a healthy flow from the under bonnet filter. I have tried easy start and it will fire for a second or so then stop, during this I can see the Rev counter moving so I don’t think it’s the crank sensor. I have also tested the cam sensor and even though it passed test I have replaced it with new anyway. I have carried out the electrical tests for the high pressure fuel system and I get 3.97 volts on the fuel filter sensor which would suggest the two pumps are delivering good pressure. This brings me to where I think the problem lies ... I have checked the pin out voltage on the fuel rail sensor. I get 0.5 volts as expected with key at position 2 but when cranking, the voltage does not rise above 0.8 volts which would seem to indicate low rail pressure. I did a leak back test on the injectors which didn’t show any leakage from the injector bleed offs and the fact that it ran perfectly well less than a year ago suggests that it’s not an injector leak back issue. I have also changed the seal on the high pressure pump regulator (the one behind the starter motor), the old seal was intact but I changed it anyway. One thing I noticed when changing it was that there is a flexible seal and a plastic backing washer, the backing washer appeared to be cut through like a piston ring. I guess that’s so that it can be fitted over the shaft or could it be broken and that could be an issue causing leakage? My question would be where else could I look to find a cause of the low pressure in the fuel rail? One last thing, I am in south east London and nowhere near a T4 session and the car is SORN and totally immobile. Any advice on my problem would be much appreciated. Best Regards, Mark

11th June 2021, 12:00	#2
dave lincs Posted a thing or two Rover 75 Saloon Join Date: Mar 2014 Location: Louth Posts: 1,409 Thanks: 380 Thanked 986 Times in 476 Posts	Does the oil pressure light work on the dash?

11th June 2021, 14:31	#3
COLVERT This is my second home R75 Saloon. Join Date: Feb 2009 Location: France/or Devon. Posts: 14,003 Thanks: 3,851 Thanked 2,167 Times in 1,816 Posts	You seem to have done a thorough check of just about everything that might make it a non starter.--- You didn't mention the battery or its state of charge. If there is too great a voltage drop caused by the starter motor the ECU will sulk and not come out to play.--- If you have jump leads and access to another charged battery then the extra current available might make a world of difference when trying to start the engine.--