Leak-off test results for C3 1.4HDi 16V

JamesQB · Unread post by **JamesQB** » 17 Oct 2009, 01:35

Using the leak-off kit I made (here's a pic of it while it was running):

I got these results after leaving it idling for around 30-40 minutes:

The moment I started the car, I saw the fuel shooting up the tube from cylinder 2. According to the united diesel website, a 10% variance is permissible. Oh dear, if that's right, then my results aren't good (hopefully my maths is, though). I carefully drew a line at the diesel level on each bottle, then emptied diesel, cleaned bottles, filled with water to the lines, then measured that water. I'm counting cylinder one as being closest to the flywheel/transmission end:

Cylinder 1: 75ml
Cylinder 2: 400ml
Cylinder 3: 160ml
Cylinder 4: 100ml

Using the lowest amount as 100%, that gives:

Cylinder 1: 100%
Cylinder 2: 533% which is 433% more than cylinder 1.
Cylinder 3: 213% which is 113% more than cylinder 1.
Cylinder 4: 133% which is 33% more than cylinder 1.

So, far more than a 10% deviation between injectors! Need to find Delphi EJBR01001Z injectors at less than the price I've seen around the net of 260 quid plus, each. Tried scrappers and even a chinese company knocking them out, but no joy.

Is it simply wear between the precision-made components of the injector responsible for excessive leak-off, or can varnish and gum build-up, etc., cause it?

wheeler · Unread post by **wheeler** » 17 Oct 2009, 08:52

Are the injectors programed correctly to each cylinder in the ECU ? I would just make sure thats correct before condeming the injectors, If thats ok then it looks like you've found your fault.

HDI · Unread post by **HDI** » 17 Oct 2009, 10:59

I would say #2 injector isn't opening or opening very little.

JamesQB · Unread post by **JamesQB** » 17 Oct 2009, 12:52

I don't know if the injectors are correctly programmed... the fault of hard starting and lots of white smoke, along with the bag of nails noise started all of a sudden years ago now. Trying to talk family members who also have Citroens into clubbing together with me to buy a chinese lexia 3 so I can check things like that myself.

Regarding injector 2, if it wasn't opening properly, wouldn't that cause the opposite condition of less leak-off? I've got the delphi manual and have been trying to understand what's going on. I see that when the injector solenoid is activated, a valve raises which connects the discharge orifice from the pressure chamber at the top of the needle to the diesel return, so assumed no fluid flowed through unless the valve was raised and therefore the needle was raised too by the pressure imbalance?

Xantidote · Unread post by **Xantidote** » 17 Oct 2009, 17:31

Well done. Impressed with the test. At least you've pin-pointed the problem

Martin

uncle buck · Unread post by **uncle buck** » 18 Oct 2009, 00:37

Just goes to show we are being sold a load of trouble with this modern computer controlled mumbo jumbo.....I would much rather have a mechanical injection system...at least that was fixableby mortal man....

I truly believe this is being done on purpose....in today's age we have the technology to build a car that doesn't have this type of fault, I'm sure we do...but where's the money in that...ehh !

Anyway good luck with your problem...looks like injector # 2 & 3 are iffy to me....# 2 being the worst.

Cheers.

JamesQB · Unread post by **JamesQB** » 18 Oct 2009, 19:50

I also believe the same. When it counts (like aeroplanes) things rarely go wrong so catastrophically and so readily. These parts are designed to fail, just like most electronics goods. It's becoming increasingly common for TVs et al to fail shortly after warranty - now that's clever workmanship!

Of course, it's all about the money, especially when these parts are being sold for obscene amounts and without them you have thousands of pounds worth of scrap metal. Citroen's price for the EJBR01001Z injectors used in this car are £326 each. Think of other high-precision things you can buy for other applications that cost a fraction but are equal in complexity. Add together the cost of all replacement parts available for the C3 and you could probably buy 3 or 4 brand new C3s for the same.

I'm looking at HDi injector overhaul specialists now. Found a list on the Delphi site of places that are official Delphi ones and have the ability to make new 16-digit c2i tolerance codes after overhaul.

steelcityuk · Unread post by **steelcityuk** » 20 Oct 2009, 10:25

How can you guys actually believe that parts such as injectors are made to fail? Could it not be a fault in the production process or faulty materials?

How many airplanes have fallen out of the sky (as a percentage of number built compared to cars) or how many NASA missions have failed because of malfunctions, now you can't say they use parts built to fail.

Generally components are made to a price/profit margin and this could be the problem. Where modern diesel injector are concerned they are made to extremely fine tolerances and so are expensive to make and easy to break.

Everything can/will go wrong at some point mechanical, electrical or biological.

Have a look at Feather Diesel's site for parts service - http://www.feather-diesel.co.uk/ They have a good reputation.

Steve.

MikeT · Unread post by **MikeT** » 20 Oct 2009, 12:36

I'm in total agreement with Steve though there are rumours that certain "chips" in comsumer electronics are programmed to fail after a given count/time - but if so, that leaves the doors open for court claims IMO, so not a clever idea.

The reason aircraft don't appear to fail as often is probably due to the many backup systems incorporated into the finished product. Even our cars do have "limp home" mode which itself is a sort of backup and does get us home whereas without it would leave us stranded.

I think Steve is right because it's obvious that manufacturing company's want to charge western prices (based on western quality) yet outsource or build their plants/factories in eastern countries due to cheaper costs - which is a rip-off/con IMHO. Although BOSCH (for instance) may have high standards and QA strategies, that doesn't guarantee they will be understood and adhered to (in India for instance) due to the cultural differences and local materials etc, etc. For example, it's been shown that injectors from one factory can be of much lower quality than another, even though they're sold as identical parts.

JamesQB · Unread post by **JamesQB** » 23 Oct 2009, 01:26

My next step is to club together with family members also owning Citroen cars and buy a chinese Lexia so I can input the new C2i codes of any overhauled injectors into the ECU. Only Delphi authorised repairers can supply a new code yet their price is the same as another place I found which cannot give new codes. £105 compared to £326 for a new injector is very good and once I have a Lexia, I shall be sending off number 2 injector for overhaul and going from there.

God willing the end of this car's troubles are in sight!