1996 xj6 x300 3.2 automatic. When coming to a stop (traffic light) if I keep the transmission in Drive, footbrake on, the car has a jerky movement on and off as if it is trying to move forward.I checked the rpm and that does not seem to fluctuate, that is why I am thinking transmission. Anyone have any ideas where I should start looking ?

 

I suppose I would start looking at the transmission fluid level and find out if it's due renewal. I trust the engine idle is smooth when in park or neutral?

 

thanks, I will renew the transmission fluid. Just bought the car so do not know it's history.Yes, when she is warmed up the idle is smooth,just to complicate things,yesterday there was no problem ! So I guess it is an intermittent problem that makes it very hard to find.Elimination of the easy things to do is the best way to go.Another question, when cold she idles very rough,like misfiring on one or two cylinders, but as soon as I hit the gas,she runs smoothly. Ideas ?

 

I don't know about the 3.2 model cars but the XJ40 4.0 with the ZF 4HP24 had a fault with the Torque Converter Clutch locking at slow speed and stalling the engine. Customers would complain that the engine tried to drag the car forward and when the brake was applied the engine stalled.
The fault turned out to be a low fluid problem and when the fluid level was corrected the fault did not reoccur.

Jaguar issued a TSB for the problem but I can't find it now. It was issued in the early 1990s

Just something to consider.

It might be a torque converter fault????

bob gauff

 

Brent, all the above are SPOT ON.

My 3.2 did that when I first got it 3 years ago, and fresh fluid did wonders.

The "kick down" cable on mine was set too tight as well. Like Bob, I cannot find the paper on it at the moment, maybe in the old laptop that died, so gone forever??. I basically wound the adjuster (at the throttle spindle) inward (slackening the cable) a half turn at a time and kept at it until I was happy with the downchange as you slow to a stop, and the upchange as you drive off.

I then had lengthy discussions with ZF here about using synthetic trans fluid, and the advice was to "go for it", and to introduce it gradually, was their best advice. I simply undid the dipstick nut and let it drain, refilled with synthetic ATF, and did it again a week later, and so on until I believed I had sufficient synthetic concentration (about 6 drop and fills), and then did it once more with the pan off and a new filter.

WELL, the difference was nothing short of amazing, and I am NOT easily amazed, trust me. The silence from the transmission was the most noticible at about fill #4, and the gearchange quality improved significantly at about the same time and continued to improve to the point that now you have to be "real good" to pick it changing gears either up or down.

I did the same with the power steer fluid, using synthetic ATF, and the annoying "whirring" from the pump is now a thing of the past.

 

This is more than likely spark plugs in dire need of replacement.

The dreaded "black goo" inside the throttle body may be giving some grief if it has not been cleaned recently. I do mine at every oil change.

Of course many other items may be involved, but as you said the simple stuff usually sorts most engines, and Jag are no different.

 

Guys, Thanks so much for your inputs. I will do all of the things that are mentioned here next week and then give you all an update,again thanks

 

Grant, I am not sure about the adjustment of the kick down cable. The problem I seem to have is that before she changes to 4th gear I have to be doing 80kph or higher. according to the specs it should be around 40kph. So what adjustment do I make to lower my gear change down ?

 

OK.

These are a "dinosaur" transmission, meaning they are not electronically gear change controlled. There is a cable from the throttle spindle to the transmission internals.

Look at the throttle capstan, you will see 2 cables attached. On my RHD they are both at the 3 o'clock position (or very close to that), and the throttle cable is the "lower" of the 2, and has a metal adjuster, and steel lock nuts. The upper cable is the transmission cable and has a black plastic adjuster. Loosen the locknut CAREFULLY, this thing is plastic, and turn the adjuster inwards, so lengthening the cable.

I wound mine all the way in, until I could "feel" slack in that inner cable, then wound it back out until it just took that slack out the cable, and then ONE full turn further outwards.

I have done this adjustment toooooo many rimes on tHE old BW65/66, even an old DG long ago, so I have the "feel", and it makes it simple. It is NOT rocket science, trust me, and if yours is hanging until 80kph until 4th comes in, that cable is my FIRST guess, then valve body sludge, low fluid, neglected fluid, etc, etc.

Mine changes into 2nd to 3rd at 40kph approx, and 3rd to 4th at 56kph, with very light throttle, and 63kph with "normal" throttle. The "lockup" is at 82kph, under all but real heavy acceleration. We have these dumb 50kph speed limits here, so light throttle is most of the time.

If this cable thing is still as clear as mud, let me know your email and I will Kodak mine and PM you the info, no problems.

 

Mine has about almost half inch of slack in it right now.The fluid is at the right level and a beautiful newcolor look to it.Tomorrow I will tighten up the cable until it has no slack and then try it again.Let you know what happens. Cheers.

 

Brent,

Just read your post some more, got sidetracked last night.

With that much slack in that cable, the trans would/should change "up" very early in the KPH range. I then reckon the 82kph change you "may" be describing is the "lockup" feature, coz that is the speed it happens at, and is NOT related to that cable at all.

I also reckon you may have a valve body that is quite "mucky" from slack trans servicing prior to your ownership. The fluid looks clean NOW, but the muck in the valve body needs something a bit more active to clean it out. I HATE additives, but a trans treatment may assist in this cleaning, and then a pan off service with a new filter etc would do wonders.

That adjustment you will do is also a top idea, as then the gearchanges should get somewhere back to spec.

 

Oh what fun ! Tightened up the slack.Then warmed her up and went for a run. The only way I can describe it is if I had switched on the sport mode(which I do not have)Almost max rpm before change up in all gears and with a wicked neck snapping change.Needless to say have reverted to original setting,but it was fun to feel the power and fly along. So 4th gear then changed at just over 100kph.Maybe the "lock up" as you said. I have ordered a trans gasket and filter,even if it is not that, cant hurt to change oil and filter.(He say's brazenly)Will see in a couple of weeks when I get the filter and gasket(ebay)Costs an arm and a leg AND a head here.

 

Hahahaha, what a sweet result, for now.

The understanding I now read into what you said is a lazy valve body working bits.

There are 2 ways of cleaning it.
1) is to drop the pan and remove the valve body and physically clean all the workings, LONG job, and EXPENSIVE if jobbed out. I would NOT do it that way, as auto transmissions can be fickle if you have improper dust free work areas, and a lack of experience.
2) use an additive and give that trans some regular fluid changes to "flush" the goo out of the workings. It does work, I do that on many.

Spoke to ZF again today on another matter, and mentioned yours, and he advised a fluid flush, GRADUALLY, and using synthetic fluid was his preference, and that will slowly sort the valve body and the lock up smoothness also, as some of them can be "harsh" due to improper fluid maintenence. He also mentioned that the adjustment of that cable is "basically" take it until ZERO slack, then ONE full turn further OUT (shortening), and that is deemed close enough, and some fine tuning later as it sorts itself is easily done.

 

Yes,I read that thread. Was thinking of doing the changeover to synthetic.just don't know what fluid is available here right now.Something to check out.On a topic entirely diffrent,the favorite key fob thing.My SLCM is 315, my rear security antenna is 315 and of course my key fob is 433,Question: can I change the SLCM Module complete to 433 without causing problems anywhere else ?

 

No idea.

I looked at all that with mine, and simply got a "Steelmate" interface, on special on the day, attached it inside the drivers door, and located the 2 trigger wires in that door loom, unlock and lock, and spliced into them, and now have remote locking etc, and all for $65. If I hit the "unlock" button prior to the "lock" button it arms the alarm. If I hold the "lock" button it shuts the windows, arms the alarm. NO sunroof, poverty pack Jaguar.

Mine did not come with the fobs??, but I established all the "stuff" is fitted to the car. A simple phone call to Jaguar Parts sorted that decision real quick $325 each plus coding, HAHAHAHAHA. The "..bay sites" were useless in my opinion.

 

more info on that "Steelmate" please.

 

Steelmate is just a brand name among hundreds of "remote central locking interface moduless" out there.

I ended up with a 4 door remote central locking kit, as I said on special for $65. The interface only kits were $70.

I removed the door trim RHD, drivers door. Located the small loom coming from the door lock, and picked the "orange/yellow" as the LOCK, and the "purple/orange" as the UNLOCK wires.

Powered up the interface, and with a volt meter, found which wires actaully "fired" when the remote buttons were used, and duly marked, memory is basically toast.

I then established that the Jag system is "earth pulse" for what it does, so 2 relays (one for lock, and one for unlock), wrapped in foam in the door panel take care of that, with the interface triggering the relays which momentarily "earth" the selected wire, and the system does what it does.

I found a 12v LIVE wire (Brown solid on Jags), in the door switch panel, and simply spliced a wire from that to feed the interface and the 2 relays. Then used one of the Black wires for the earths, as attaching earths simply to the metal panel, relies on the door hinges for an earth path, NOT good.

Some interface units do have the Earth Drop feature, but the one I got did not, so I adapted, Aussie style.

Took 2 hours including drinks and interruptions.

 

Bought the SLCM with 433 on it ,changed it over and now everything works as it should,so interchange is possible if you do not(seems impossible)know what key fob frequency you have.Basically if everything on the car works,trunk lights etc, but the fob does not,check your SLCM,and swap it out for the other frequency, also it seems to be cheaper than gambling on key fobs at $50 or so a shot and no surety about frequency.The Security antenna type makes no diffrence,works on both frequencies.

 

Plus my previous question about jerking when stopped at traffic lights........well after all that trouble with transmission,fluid,cable etc. I pulled the plugs...all looked new,coils and boots perfect,then I noticed a little brown coloring around the plug where the ceramic joins the metal, on one plug.So,having no history of this car,I changed all the plugs and put in Iridium ones,such a big difference in performance and no more jerking ,even when cold.Acceleration a lot better and smoother.Still changes into 4th at 80KPH,and cable is at maximum adjustment now.I can live with that.