2001 XKR Lacking Power

[RMA37]

Nice idea Mike. This is always on our pre-flight check list and access is usually very easy. However, the lowest point on these tanks would make it almost impossible to access. A boss would need to be welded to the tank, something most welders would shy away from, and I think the MOT inspector might have something to say as it would be a modification.

The alternatives I've discovered are: running the engine for a while each week when laid up; keep the tank full whenever possible, and/or use the higher octane fuel which doesn't contain Ethanol. You would still have to allow for condensation though.

The XK8 is a great car, but I'm afraid it's another design fault!

[davidr]

The Renewable Transport Fuel Obligations (RTFO) regulations are the key here. This appears to require ALL road transport fuel to contain 5% from sustainable and renewable sources. This means ethanol for petrol and vegetable oil for diesel. This will rise to 10% in 2020 I think.
I'm the first to say that I'm not an authority on the RTFO but from my brief research I looks like anything you're going to buy on a petrol forecourt will have ethanol.
I think there are some specialist fuels available that do not contain the 5% but they are expensive both because of their low volume and a tax surcharge of something like 30p per litre for opting out of the RTFO.
It looks to me like a full tank and fuel stabilisers are the answer for cars that aren't used very much.

[RMA37]

Yes I would agree with that David. It looks as though the regs originated from the EU and have now been revised by our government in advance of Brexit. Where it will lead eventually I don't know, but one way or another they make it increasingly difficult to use the cars we already own, My BMW will not run on Bio Diesel and I'm not thinking of changing it yet until governments the world over can commit to a decision for longer than the term of office.

[J44EAG]

Exactly the solution I`ve just been chatting to David about.

I envisaged a new, un-used off the shelf tank that had never previously held fuel. A spigot could certainly be obtained or made and then welded to the bottom of the tank. David tells me the valve would have to exit the car via the boot floor and would probably have to be located above the diff cage. Access would be impossible.

Great idea though, eh?!

Pump fuel. At an Esso fuel station to day. I can confirm I`ve seen that E5 is contained in both standard and premium grade fuels. I think we all need to begin to use fuel dryer additive more frequently having seen the damage caused to David`s internal tank components. Not nice or funny.

Mike K

[RMA37]

I'm sure David's car is not the only one, there must loads of hidden horrors to be discovered. What I find annoying is why the components were made like that in first place. Water in fuel tanks isn't new, so why make things that will rust and malfunction in this way, particularly in a supposedly high quality Jaguar. I accept that we can't foresee what future fuels will be and the effect they might have on our cars, but we did have the knowledge that water will rust steel!

I've been doing a bit of research since this cropped up, a bit like self diagnosis when you have a pain, and there's an awful lot of info to be found, some of it quite scary. I'm an engineer not a chemist, but the proliferation of products to do this that and the other to our fuel systems is mind boggling. Wynne's for instance do so many (essential according to the ad), if we used them all we wouldn't get any fuel in the tank!

On one site I read that if Ethanol is added at more than 15% older cars will have trouble not only in the tank, but the whole fuel system. Apparently 10 to 15 % is recommended in the US, so we might see that here.

As I see it we have two options. Drain everything down and just look at your car or, keep on driving. I'll opt for the second!

[davidr]

The answer is to keep using it!
Mine has not really moved for about 7 years.
Regular fresh fuel and a good thrashing is the answer!

[J44EAG]

....AND most importantly, dose with dry fuel additive and also injector cleaner. I dump gallons of the stuff in the XJR simply because I used to see so many horrors when tending customers boats. Protective maintenance in a bottle can only but help.

Mike K

[RMA37]

I'm a bit confused about this. I've never put any additives into fuel since the days of STP when that was all the rage in the 60's. Having read the directions for the Wynns Dry Fuel additive, it says to put a complete bottle full into the tank every 6 months. OK, that's fine with a full tank, but when you use the car and top up with fuel, the additive is slowly diluting and reducing it's benefit, which could have long gone before the 6 months is up.

I can understand when you leave the car for any long period, but then it's not helping to clean the injectors, which is another claim. I'm all for preventative maintenance but how do you measure this one?

[davidr]

I popped down to Hollygrove this morning as the replacement tank from EuroJag arrived yesterday. Good news is that this new tank is clean as a whistle inside and out. Bad news is that despite us asking for the sender to be included it wasn't which meant that we couldn't put it in today. The guys at Eurojag were decent about it and have put one in the post for us foc which was good of them.

The old and new tank together - old one closest. Even the outside of the tank is cleaner. Wait until you see the insides!

These rust flakes are in the pick up bowl in the old tank. It's scrap!!

This is the kind of rust that was inside the tank

The sender unit was rusted up and not moving freely

We've built up the new tank with new pumps. Just waiting for the new sender unit and then it's ready to go back in

This is the condition of the inside of the new tank

Hollygrove tell me that before taking the tank out they ran it on the second pump and it drove as it should so I'm getting more hopeful that this fix will do the job

[J44EAG]

Certainly a very nasty old tank. The new one should help you out of the present situation. Lets hope you get a quick and satisfactory result.

Its been a long flog for you.

Mike

[RMA37]

Great set of photos David, thanks for keeping us informed. I can't remember what the fuel filter looks like, but regular inspection of that might indicate what's going on the tank regarding water damage. I'm in Spain at the moment having just endured the worst storms in Spanish history (plenty of water here!), so I'll have a look at mine when I return.

Good luck with the rest of the assembly and I'm sure you'll be hearing it running again soon.

[davidr]

The fuel filter is up under the driver's side sill and is a traditional cylindrical type.
As the pumps themselves have a primary filter the condition of the main filter may not help!

The pumps each have a filter bag over their inlet as above. This also shows the state of my fuel pumps

[davidr]

Good news! We put the new tank back in today, filled her up with fuel and off she went!
So the replacement sender arrived during the week and it is spotless so we were very happy to put it in.

I had thought that the boys at Hollygrove had put new pumps in. They certainly looked new but I found out today they haven't but did have a pair on the shelf. So we took the existing ones out of the new tank and they were spotless. They didn't even smell of fuel so I'm guessing that Eurojag replaced them before sending the new tank.
Anyway, just to be absolutely sure we fitted the new ones and the sender and wiggled the tank back in, connected everything in the boot and pushed the car on to the ramp so we could get underneath to connect the fuel lines. These are up above the diff where you can hardly see them let alone get a hand in but we managed to snap in the quick connectors somehow!

We put about 2 gallons of fuel in and cycled the ignition a few times to build up pressure. The fuel pressure gauge was still on it and that showed healthy pressure that was also holding when the pump stopped which was a good sign.
The car started happily and so I took it down the lane and she went beautifully!
So now the car has achieved the status of a rolling restoration!
The drive home as all good. God these XKRs can really shift when they want to! No problem with getting enough coals to the fire now!
The only thing I did think was that the gearbox was being a bit slow to drop down when I put my foot down. Following the issues with the TCM it presently has one from an XJR of the same vintage. That has the same engine and gearbox but I wonder if it's set to be a bit more genteel in its behaviour? It appears to change up quite early and be reluctant to change down. No issue with the operation of the gearbox which is lovely and smooth.
So the game moves on to the next steps.
I'm quite enjoying all this as I'm learning at each step!
Happy days!

[RMA37]

Great news David, and thanks to your very comprehensive reporting, we are all learning.

[J44EAG]

Nice one, David. What a flog this has been.

The gearbox is I believe adaptive and might take time to learn your driving style. It might we worth considering having the gearbox re-flashed to ensure the gearbox and ECU are talking from the same page. A re-flash is common procedure after having a gearbox oil service done. Just a thought.

I recall that with many Jags of a similar time line that you can teach the gearbox your driving style by belting the heck out of the car and keeping your foot on the brake pedal for thirty seconds after you switch off. This logs your style into the ECU for future driving. Can`t remember much more on the subject though.

Remind me to show you how to tweak a V8R next time we hook up. Small pulley, Gerald ECU reflash, decent air intake and modified throttle elbow and charger ramp profiles. Something to do over the winter....

Mike