Jaguar XF 3.0d Project part 8

Published on 23 April 2024 at 09:50

Sod it to sodding soddery, this isn't how I expected a trip to the shops to end.

It's quite daunting when you look under the bonnet of a modern diesel. Most of that crap is anti emission stuff, much of it saps power, stuff like the DPF and EGR's cause endless problems thanks to rushed in legislation and poor design.

It's all a bit tight in there but not too bad, you have to be careful though as everything is very brittle, easily broken and usually expensive to replace. It's important to take your time, take photos if you are not sure and mark anything you take off,  this is particularly important with the very latest diesels where injectors are individually coded to the ECU. The Jag isn't but they will be replaced in the same order anyway.

Number 6 - left hand side nearest the back was the worst to get out, I suspect putting it back in will be fun too. Not too bad a job though, much easier than I had thought.


I would be surprised if these are more than 1000 miles old, somebody would have paid about 1000 quid for these - 2/3 what I paid for the whole car. Doesn't bear thinking about. The big shiny nut on the top one was because that injector was a bit tight and I needed to get some pliers on it but didn't want to damage the thread. It's a UNF rather than metric thread.

When I wrote part 6 of this never ending saga I thought that was it for a while, yet part 7 came along pretty quickly and here I am writing part 8. I am sat here at my pc, stinking of a combination of diesel, sweat and frustration, yet there is hope. Let me explain - those of you who read part 7 will know that Vin the Diesel came home on the back of a transporter on Saturday, a most disturbing noise was coming from the engine bay and the car was not starting as if the engine appeared to be seized. The following tale is one of mis-diagnosis and one of hope tinged with stupidity and a lack of familiarity with the witch craft that is modern diesels.

I started off this morning thinking that I would find a garage to have a look for me as my confidence in my ability to sort it was pretty low - had it been a petrol car it would have been a no brainer but my experience with diesel is virtually zero - I have had diesels before but nothing has ever gone wrong on them engine wise. I tried 5 garages, none could help or would help. The two nearest me are up to their arm pits in work and both have 1 mechanic on leave, the nearest Jag specialist is now booking work for May, one other wouldn't even consider it and my first choice of the guy that did the cam belt for me is snowed under as well.

After thinking about it and having a sanity check with my mate Malc I had decided to have a look myself and if I couldn't get anywhere I would break the car and get some money back that way.

I had already dropped the oil and seen nothing bad in there, inspected the coolant and seen nothing bad in there, smelt the engine and smelt nothing bad, I knew it hadn't over heated I started to doubt that there had been a major failure. Much research was done over Saturday night and in to Sunday and I had determined there were a few different possible scenarios, the one that seemed to make the most sense was a stuck injector pouring diesel in to one of the bores, the knock definitely sounded like one cylinder, a flooding bore would definitely cause a hydro lock, which would stop the engine turning. There was no way I wanted to do any further damage if that was the case so the first obvious step was to pull the injectors. It's a tricky job, things are tight in there but soon all 6 feed pipes were off, the return pipes were off and the electrical connectors were off.

I had heard of specialist tools being required to pull the injectors so I was very surprised when the first one came out with just a wiggle and hand pressure, I was even more surprised to see it was brand new. My surprise grew at each step as one after another the other 5 brand new genuine Bosch injectors came out. Somebody has recently spent about 900 quid on the bloody things, there was no sign of flooding in any of the cylinders.

Ok, I thought, I wonder if the engine will turn - only one way to find out, I cranked it half expecting it to just lock up like it had done on Saturday but it turned over freely without any knocks or bangs - fantastic, the engine is probably ok after all.

The only question in my mind was then - why didn't it crank on Saturday, it had a brand new battery in, I knew the alternator was charging from where I repaired the monitor system and no warnings had come up on the dash. Just to make sure and to continue my diagnostics in a sensible order I checked the battery voltage - 11 volts, that's why it wouldn't crank!! The second question was - so what was that noise and the third question was what's up with the battery?

I came in for lunch as I had a few things I wanted to look up and video popped up on youtube that gave me hope, inspiration and the will to carry on - a bloke with an engine that sounded exactly like mine. I watched the whole thing, his problem was leaky injector seats causing what he called injector chuff. I wasn't sure if I was fooling myself so I passed the headphones to Mrs Dave and asked her what she made of what she was hearing, she immediately said that was exactly what our car had sounded like. When the guy started his car at the end it sounded perfect  I think that is what my problem was.

I have ordered new copper seats, new o rings and new stretch bolts - sadly the bolts the injectors are held in with are single use, a new set is 25 quid. The  seals came to about the same again but if it fixes the problem it's a very cheap fix indeed. Inevitably a couple of things broke while I was spannering, everything is 14 years old now and lots of plastic bits are brittle, particularly some sort of balance pipe that runs over the back of the engine, it fell in to several pieces when I  tried to move it out the way. I can make a new one no problem- 3/16 copper brake pipe seems like the ideal material for the job and I have a roll of that. It will be at least a couple of days before all the bits arrive so I can do that in the mean time. I will leave the battery on charge for a few more hours, it seems to be coming up slowly but I think I may well end up having to take that back. It has a 4 year warranty so doubt it will be a problem.

i won't know for a few days now but I have a lot more hope than I had on Saturday, I had talked to Mrs about breaking it to recover my money, I really hope I don't have to because it is a beautiful car that is a joy to be in, I have also spent a hell of a lot of time on it and most things were fixed. I am not going to do any of the remaining jobs until I know things are back to full health in the engine department but I have a good feeling that it will all work out in the end.

I have continued to look in to this problem while I wait for parts and I can't help thinking there is a link between the battery going flat and the car failing. I'm still pretty sure the noise was down to fuelling as everything mechanical seems fine. I know that these cars are very sensitive to voltage drops, I can't help wondering if the two things are linked - often when 2 problems occur at the same time there is a common cause. I have ordered the parts I need to reinstall the injectors - the copper seals, o rings and stretch bolts all have to be replaced with new if you remove and replace an injector. Sadly after years of tolerating numerous pot holes on the road to my house, the council chose today to close the road and dig it up, the courier that was delivering my parts could not get to me so I lost my chance to get on with the job. Today is Wednesday, rain is forecast for the next 2 days, Saturday I am going to a rally, Sunday is auto jumble day so it's likely to be next Monday before I can make any progress at all.

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