I have a V6 2004 Jaguar S-Type with 62,000 miles that I have been having some trouble with for around 4-5 months now (just days after an oil change at Valvoline, not sure if it is related but just in case thought I would mention it). I had posted about 3 months ago (maybe more) about a problem with my car's rpms fluctuating while driving and the general consensus seemed to be that I needed a reflash of the TCM or I had a bad battery. I unfortunately was laid off the very next week and could not go and get this done. However, now I am thinking the problem is something different completely, due to new symptoms, and wanted to see if anyone could help me figure out what is wrong with my car.


Symptoms are:

1. For the last 4-5 months the RPM's fluctuate when driving around 35-45 MPH, but not when idling. They jump up and down by roughly 200-300 RPM's (it seems to get worse when it was cold but does it whether it is hot or cold). It does not happen everytime I drive the car but around half the time or slightly more.

2. For the last 4-5 months when I start my car a loud metal clanking or rattling sound comes from the front of the car. It only lasts a few seconds, when I turn the key to start my car, and stops immediately after starting. It is very loud, sounds like metal rattling and happens roughly 60% of start ups.

3. Just recently, within the last 2 or 3 days, when I turn off the ignition after driving, the car starts rapidly beeping repeatedly (probably 2 beeps a second for several seconds). I believe it is a warning beep, but no dash lights are lit up.


4. I have also noticed that after the car is running for awhile I can sometimes feel what seems like the engine cycling, maybe it is a symptom or I am just noticing more now do to the other problems, but it does feel different than before. The RPMs do not seem to fluctuate when this happens.


If anyone could please give me any ideas on what this might be I would sincerely appreciate it. Thank you.

 

Sounds like the timing chain tensioners.. Trust me I know...

 

Howdy stranger!

OK... Quick and dirty... PM me, take a quick ride to Akron, let me hook my scanner up to it and we'll take it for a test drive.....

My guess is the beeping is not related to the rest... We need to check your shift linkage cable bolts before it becomes an issue...

Sorry to hear of your troubles, wondered what happened.

 

Aha! Go see Jeff!

He'll also listen.

The beeping could be that the car sees the shift lever as not in Park.

Sorry to hear of your woes.

 

Helloooooo??????

 

The RPM fluctuation at low speed may be worn O2 sensors. There are four (two upstream, two downstream). The clanking may be timing chain tensioners or worn accessory pulleys.