Hello dear Jaguar Forums,

I am working on an old 2002 Jaguar S-Type 4.2 V8. The car had stood the last two years. He starts and runs immediately, however, he has the problem that the engine runs pretty rough and shaky.

My guess: One or more cylinders do not ignite - So spark plugs and / or ignition coils maybe defective. I have not been able to access the OBD since the battery of the vehicle is dead. (Will be renewed in the next days.)

Is such a problem with this V8 model or other engines known?
Do you think I am right with my assumption?

I have also created a video of the engine:
Thank you for your assistance!

stypeler

 

You really need that OBD tool - with live data so you can check sensors and fuel trims. Not much point starting the engine without it.

 

Welcome to the forum.

Guessing = throwing loads of money down the drain. Best to wait it out until you can read the codes and post back.

Possibilities include plugs, coils, vacuum leaks, fuel, fuel filter the list can go on and on.

 

Hey,

today i've checked the OBD. It doesn't look good:
P0300 - Random Misfire
P0301 - Cylinder 1 Misfire
P0304 - Cylinder 4 Misfire
P0305 - Cylinder 5 Misfire
P0306 - Cylinder 6 Misfire
P0307 - Cylinder 7 Misfire
P0308 - Cylinder 8 Misfire
P1313 - ??
P1314 - ??


I can also hear a loud rattling from the engine. Sounds like a bad chain

Greetings
stypeler

 

Get the free download workshop manual - explains all those and their possible causes.

Not impossible but very unlikely the chain. Look at the usual causes.

Be sure to watch fuel trims and check sensors! You're guessing instead of getting every bit of data you can.

Otherwise, why not sell to someone who will do the above.

 

I agree with Jag V8 doesn't really sound like chains.

Try switching the 2 "good" coils (2&3) with possibly 2 misfiring cylinders, see if the misfires follow.

 

If that's been stood for 2 years, then the fuel would have gone off for a start.
Have you put good fuel in it yet?
Mis-fire on 6 out of 8 cylinders? I'm surprised it even started in the first place.
Take the rockers covers off, take the plugs out, set the crank timing and see if the flats on the cams are level where they are supposed to be.
It will also let you see if the secondary/primary chains are decent or not, and the tensioners.
I would also do a compression test on all the cylinders, just to be sure the primary or secondary chain hasn't slipped across a couple of teeth and clattered the valves.

 

You've actually got a 2003 model year not 2002. The 4.2 engine does not suffer with cam chain tensioner issues as did the 4.0.

The misfire codes do not automatically come from ignition problems only. The misfires could be from low fuel flow, poor fuel quality, or bad injectors.