Hi all,

I'm new to the Jag owners' scene having just 6 days ago bought a 2008 XKR. Seemed to be in reasonable nick with 62,000 miles (fine for its age) and a full Jaguar service history. The car seems to have been well looked after from the paperwork.

However, 6 days into owning the monster, I've found that it's starting to have issues. Starting from cold yesterday, the engine seemed to rock a bit, making the whole car shake. It would calm down and become nonexistent after the engine warmed up a bit.

Today, starting from cold before work, the engine shook a lot more, but again settled. Then, at lunch time, I started the car to pop back home and grab some paperwork, and the car started to rock even moreso than before, this time with the idle revs fluctuating quite sharply between (from memory) 700-1500rpm. No idea if that was the right number but it was low revs either way.

The engine fault light is now displaying in the instrument panel.

Has anyone experienced something similar? Cost of fix/is it safe to drive whilst doing this?

Ta!

 

I have had the same problem with my 07 XK occasionally when its below freezing temp outside check engine light would come on but would turn off itself around the 2nd or 3rd startup.
Cant find my code reader I know its somewhere in the house.
Just haven't taken the time to look for it so I can see what the codes are. I think this is a common Jaguar thing.

 

A work colleague has a diagnostic tool he's going to plug in this afternoon, but I'd mention it wasn't that cold this morning - around 8 degrees C.

Considering the car seems to drive fine once the engine has settled in and warmed up a bit, I'm hoping it's nothing serious! I'll see if the warning light has gone this afternoon when I start it (will have cooled down from the drive at lunch).

 

Sounds like one or more cylinders aren't firing up straight away. Do you get any smoke on startup when it does it?
I'm gonna guess bad ignition coil unit (Jags have one per-cylinder) or maybe just a bad spark plug.
Also you might wanna get your engine mounts checked just in case.

 

Update (as I can't see how to edit the OP) - I have run a diagnostics tool on the car and got error codes P0171 and P0174 coming up - some googling and liaising with a friend suggests that this is to do with the MAF. Booked in for 2 weeks from now (ugh) so hopefully should survive until then if I drive carefully and shift early, right?

 

Tell ya what..... those two codes are about a 75% chance of a vacuum leak. I'd say take a look at all your vacuum lines and see if you can find a loose, broken, cracked one. Fix that and all your problems will go away.
A quick way to find an approximate location is to spray a bit of Starting Fluid in shortish bursts on areas of your engine. If the idle goes up when you spray a specific area, chances are the leak is right around there.

 

Welcome to the forum MacGrooger,

You only have around 20 minutes to edit your own posts. After that they are locked and only a Moderator can edit them.

Jaguar use extended codes on the later models where the final 2 numbers give additional diagnostic information. In the case of the two DTC's you've read, there is no additional information so only the 4 numbers are applicable.

P017100: system too lean - bank 1
P017400: system too lean - bank 2

From the Jaguar DTC code lookup, possible causes are:

1. Air intake leak between MAF sensor and cylinder head
2. Fuel filter, injector, system restriction
3. MAF sensor fault (low intake air flow)
4. Exhaust leak (forward of catalytic converter)

Always use the Jaguar lookup and not generic decode information from the interweb or elsewhere as this can often be misleading.

Graham

 

Cheers Graham, thanks for the information. I'll see if I can get Wiltshire Jaguar to have a look at it today if they're not too busy - the nearest Jag dealership is fully booked until the 24th and I don't want to risk damage by driving around for two weeks.

 

I'm curious - I can hear a loud hissing sound from the right side of the engine when it's running. Is this normal, or could this be the cause of the error codes? Chap I bought the car from seems to think it might be a vacuum pipe come loose from overzealous revving (guilty).

Edit numero uno:

Took the engine cover off and noticed that a small black doohicky (above the A in Supercharged) had come loose from (what I assume is) a vacuum pipe. Reattached, and hissing now seems reduced. I noticed that there are two vacuum pipes leading to this gasket/whatever it's called, but only one feed to the angled rubber seal. Is it likely that the second vacuum pipe has also slipped out?