Okay, I have a 2004 S-Type. When I am between 40 - 50 miles an hour and not accelerating my car seems to be skipping/lurching. If you look at the RPMs, when the lurching motion is felt, the RPMs jump up and down and you can hear the engine making a grunting noise like its trying to go faster but just cant get it together!

I have taken it to two Jag dealers and the car has thrown no codes. Also, road test by the dealer have shown nothing as well.

Help! It is so aggravating, especially when driving with friends in the car.

THANK YOU!

 

Welcome to the forum sdgen285,

(I've moved your post from General Tech Help to the S-Type section as it's a model-specific question and should get a faster and wider response here).

Please follow this link to the New Member Area - Intro a MUST section New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to post an introduction to all the members.

Hope the guys here can help you with the skipping/lurching issue.

Graham

 

sggen285, Did this all just happen suddenly or gradually progress? The check engine light (CEL) w/codes may be on their way. A weak battery, spark plug coils, catalytic converter, torque converter and/or transmission may be at fault. When cold and thereafter, is there a rattling sound coming from the vicinity of the catalytic converters? Without a CEL w/codes, you or a competent mechanic must do some snooping around. We'll be standing by for further information.

 

Sounds like the TC - see the TSBs and HOW TOs and search if you want details.

 

Good morning! Thanks for the help thus far. I must admit I am not knowledgeable about car repair, so you will need to forgive my ignorance while I learn!

The skipping/lurching feeling has happened over time. Just started to happen more and more until it is a daily occurance.

There are no rattles or strange noises coming from the engine.

I have 100,008 on the car, not sure if that helps!

Is this just an annoying thing or is it doing damage to the engine?

 

Another vote for the lock up clutch starting to fail in your TQ. See the TSB JagV8 references for more details. This will not set a code and will get worse and worse. The clutch lining is failing and the pieces are going into the transmission fluid.

What you are feeling is the clutch locking and unlocking. When locked the car will bear down a bit as the hydraulic slip from the TQ is now gone. Then the TQ clutch can't hold the engine torque and releases the clutch. The change in RPM is the best clue.

Only fix is to drop the transmission and replace the TQ. Several people on this list have reported it and got it fixed with a new or rebuilt TQ. I recommend you start researching the best place to get this TQ.

Does the transmission work OK other than that?? The reason I ask is the transmission has to come out to replace the TQ and it would save labor if you needed a rebuild too. If not be sure and change the sleeve that is prone to leaking. I would also change fluid and the filter/pan assembly. At 108K you will need it!! Remember your transmission fluid has clutch material floating around in it depending on how many miles you drove with this problem.
.
.
.

 

Ah crap! This sounds like an expensive job and not much fun. I will read up on it!

 

By the way, the transmission runs fine other than that. The car has always seemed a little sluggish, but maybe TQ has something to do with that. I am not racing it, but also not driving the Queen of England around either!

 

Yes the TQ clutch seems to be unrelated to anything else. It also seems to be more common in the first years of the 6 speed which was 2003. The good news is it's completely fixable and does not come back.

Does not matter what the engine is either. From the V-6 to the STR it's happened to all engines. But it's not very common.

Did you get the TSB to make sure it matches what you are seeing?
.
.
.