I did a video clip because our longhorn experienced mechanic suggested that my 1993 XJ40 was shaking and that was not normal and he said there was some air running into the engine or intake .
So, this car has 160300 kms on the clock or more than 100K miles and tuned up nicely by jag mechanic .The Jag Specialist didn't report me any fault about this shaking or vibrations .
So, do you think this is normal sound or something is wrong with the vacuum or anything else ?
Let me remind you , while the video is shoting the engine is dead cold and the car is in Park

Here is the link to the engine video

http://www.youtube.com/watch?v=lsj1g4R-kTE

 

Hey Caddie, I listened to your vid a few times, your car sounds better than mine. It is hard to see the shake you mention due to a wobbly camera hand.

If you are still worried, try re-shooting with the camera on a fixed support, if you don't have a tripod, even an up turned broom will help you, as a monopod.

To demonstrate a lumpy intermitent idle you can place a plastic transparent 1 gal container flat on the valve cover with some liquid in it. A half empty screen wash container will do.

If the engine gets an attack of the shakes we will see it in the liquid.

 

Hey Translator,
I do have a tripod but I don't know if it can be attached to the cell phone , I will have to check it out .
You have a good idea , I will give it a try later
Thanks

 

That sounded (and looked) silky smooth to me!

I know a trick for the old V12's would be to stand a nickel on end and it would stand perfectly because the V12's were so smooth. I never did try it on my AJ6 engine, but I would be curious if it could do it. Although I do think that the cup of water would probably be a better test.

But back on topic; you could always take a spray bottle with some warm water and a drop or two of dish soap and spray your vacuum or intake hoses. Unless the leak was really big, it wouldnt suck in any of the water/soap it would just bubble.

 

I've just seen this thread and the video. I know it's an old post but did the op ever get to the bottom of the lumpy idle?
I've a 1992 4.0 xjs with aj6 engine, had it 2 years and always had a slight stumble/lumpy idle. It starts, and runs fine but is an annoying issue. I've tried just about everything and can't get to the bottom of it.

 

Still same , good thing is no fluctation at the RPM

 

Does yours run right in every other way apart from the lumpy idle?
I presume you have been through all the obvious things?
Performance wise, mine is fine but lumpy idle is a little annoying as aj6 engines should be silky smooth.
I've tested/replaced quite a lot of the usual suspects, sensor wise and checked valve timing etc.
Vacuum test shows no leaks although a little low at 16hg.
From dead cold, the idle hunts a little for a minute or 2 then fine for rest of the day.
I wonder if it's just age/mileage related, mine has 132K.
I'm determined to get to the bottom of it one day though.

 

Mine is just as same as yours descriptions , however I must add something that when the engine is dead cold at the very 1st start up morning , I look at my digital clock it just fadin' and just as the engine starts the clock is fine . It only lasts 1 sec or so and only happens when I start up a dead cold engine .I have no idea why lumpy idle has to do with the clock lol

 

Sorry to give you bad news, Regent, but after viewing your video I've come to the inescapable conclusion that, (in my half-vast experience), your engine is complete and utter rubbish!
You need to get it out of there ASAP, 'cause when it blows it's gonna throw shrapnel big time! You'll probably lose some major body parts and end up killing a bus load of nuns or somethin'.

To assuage your grief somewhat, I'll come by and haul that trash off so you don't have to deal with it.
Hey, don't thank me. After all, what are friends for!

(Uh ... help me out here. I punched "Planetarium" into mapquest and it wants additional information ....??)

 

Hey Retro, how are you getting along with the Chevuar, it's been a good while?

BTW folks my XJ40 has always hunted a little when cold. I seem to recall that someone once said to look at the CPS down near the distributor it can become cruddy. (although it is a dim memory).

 

I don't seem to have the issue with the digital clock.
I bought a brand new ignition module yesterday, removed old
one and cleaned up the area and gave all connections a thorough
inspection. Unfortunately the new module was faulty! Car would not
start, put old one back on and ok again. Typical. Place I bought it
from have refunded me and said just bin the faulty unit.
Incidentally, code ff44 came up again yesterday (lambda sensor).
Car was started from stone cold, I had only been driving for 5
minutes, temp gauge was at about a quarter. I came to stop at a
junction and engine began to splutter for 4-5 seconds then check
engine light came on and engine seemed ok again after that.
Am I right in thinking that the lambda sensor signal is only used
by the ecu once engine is up to a certain operating temperature i.e
fully warmed up?
Is code ff44 flagged solely by lambda sensor or are any other
sensors considered?

 

Hey thanks for all the replies,
hey retro turn your knob to bob , even if you give bad news it's good to see your input here , you know I like your sterling opps I mean your styling lol

hey jonnie , you better digg up XJ40 Forum for your symptom or post a new thread in General Tech Help sorry bud I can't give you an idea how to fix it

 

Regent & Translator,
Thanks for the props. I've been hitting the site daily, just being (blessedly!) quiet.
As for the Jag/Chevy project, it's still on the front burner .... unfortunately all the fires seem to be out in the stove.
Life keeps getting in the way ... (mostly naps, I'll admit).
D'ya think I may be motivationally challenged ...???

 

Retro, Maybe you should try one of those 'special' courses where you run around the woods all day shooting paint at folk, before erecting a shelter made from bits of branches and bracken, and then spending the night in a monsoon, followed by, attempting to light a fire with a lump of flint and a nail, in order to cook your breakfast of freshly caught gastropods over steaming flames.

I hear that this is highly motivational.

 

Thanks. I'll start a new thread. If I ever find a solution, I'll let you know, maybe cure yours aswell.
Cheers, jon

 

Jon, you may want to look at this from the archives.

 

Well, maybe so .... but motivated to do what ...???

This is Mississippi ... we don't do wussy paintball, we go live!

Mmmm-mmmm, loves me some gastropods.

Yeah, I know a little about artistic/literary license, but don't you think "steaming flames" might be a little over the top?

Sorry Regent, didn't mean to hijack your thread ... I'm outta here!