My 2001 xj8 had a new, high pitched sound when I started it, that changed with the engine's rise and fall. It was different, but not loud, and I drove it .25 mile to a class and then home again. On the way home, as I turned, something went THUNK under the floorboards at two turns. I cannot for the life of me figure that out. There was nothing in the road.
Husband checked the fluids- power steering fluid is low, we are filling that. Everything else is fine. No lights are on. Any ideas what is going on? I am not driving it, I am scared of the thunk.

 

The whine could have been the power steering fluid low on fluid. Has it gone away now?

My guess is that the thunk is unrelated. Suspension or subframe bushing?

 

[QUOTE=Streambed;1555367I drove it .25 mile [/QUOTE]

Is this a typo or did you really only drive it 1/4 mile? If so this isn't going to be doing it any favours and is an invitation for transmission failure.

The whining sounds like the steering fluid being dry as mark said, but if it's still there after top up it could be the Power steering pump.

 

I have a class .25-1/2 mile from my house so I drove it to the class after it made the sound.
We topped it up and the sound lessened but is still there. The power steering pump was replaced 2015, though. I am going to drive it this afternoon for a while to see if the sound goes away.
Are you saying it is a bad idea to drive the car short distances in general?

 

Lisa, it is a bad idea to drive any vehicle regularly on very short journeys.

The engine, transmission, diff do not get up to temperature, therfore the oils are not working to protect the units efficiently.

More than 75% of engine wear occurs during starting/ warm up.

 

This is what killed the transmission on my old XJ, I had a commute that was only 1.2 miles and 7 minutes to drive. I would do this twice a day sometimes four times a day and then one day there was a nasty crack and that was the beginning of the end for my old Jag.

In hindsight I was quite ignorant of what I was doing driving to work such a short distance, but I had a lot on at that time. Now I have a small 1.2 litre Ford Fiesta for local work and my Jag is for journeys where I know it'll get a proper warm up.

It takes 10 minutes to walk 1/2 a mile.

 

I got a bicycle for that, no wear at all, only on my knees .

 

The problem is not the distance, it is what I need to carry to the class, which is a huge and heavy amount of stuff. It would take a bike with a wagon attached! We are testing the car today to see if the sounds will vanish after driving it for a while. I guess I will schedule outings for me and the car to Go Do Things and drive distances. That sounds fun. Well, if I can make it work, anyway.

 

We took it out and it is still whining, although a little quieter at first. There was no bump under the floorboards. Can the steering pump be damaged by running for a while with low steering fluid? If so, what would be the indicators? When should I expect the whine to stop after adding fluid?

 

Not sure on these, but most cars that I've had power steering whine after running low, almost immediately silences when it's topped back off, so if it's still doing it, it might be something more.

 

Ok, so the sound is still not gone, although it softened, and odd things are happening. First, the air conditioning speed seems to want to vary with the engine speed at times, but not always. Second, sound is louder when air conditioning is running. Third, Lights came on yesterday afternoon:
(ABS)
trac not available
and another one with the trac C something

So, we checked the brake fluid and added brake fluid.
So then today, my steering, which was easy and wonderful got grabby and started fighting me, and then when I turned it on again, it didn't want to go into gear. I put it in S mode and limped home. What the heck is going on? Transmission was rebuilt year before last by previous owner, who is a Euro auto mechanic, so I doubt that it could be that. Husband says the sound it makes sounds just like the power steering whine in videos. I'm about to give up and take it in, but I hate to.

 

There isn't a belt or pulley issue that you can see, by chance? The fact that weird things are happening with the AC and the coordinating with engine speed, I just figured I'd ask.

 

You could two or more items/ problems. How many miles on the car?

The power steering pump could be making a noise -- but you would be able to get it to make the noise as you move the wheel lock to lock with the car stationary. The steering linkage and/or the steering rack could also cause a clunk -- things get loose and steering racks can fail. A bad steering rack can make quite a clunk.

The transmission pump will also make a horrible noise if it is leaking and can't maintain pressure -- this will be engine speed dependent.

And finally -- the alternator can also make a noise -- all of these noises can sound similar. How old is the battery? A failing alternator will deplete the battery and you will get problems with he ABS and other warnings. A bad battery (shorted) can also cause the alternator to make a noise.

 

#firstworldproblems

 

Not related to the clunk necessarily, but with all the belt drive related noises, I'd take the belt off and spin the pulleys to see if any of the bearings are shot. Bad pulleys could cause issues like the noise under load, esp when aircon is kicked on, or any other load is put on the belt. It probably comes to my mind since it's what I've been fighting the past week, but it's easy to check.

 

Yes, I agree check all your components that are driven by the belt, and check the gearbox isn't leaking. Battery is suspect also because you've said you're driving extremely short distances, so the car isn't being given a chance to charge itself back up.

 

Sounds similar to what happened when the alternator on my XJR started to fail.

 

Might sound stupid, but the answer for your daily commute is an EV. Something purely electrical. No warm up time required. Just jup in, thrash it, park it up. Repeat in the afternoon...

Any fuel powered vehicle is inappeopriate for these distances.

Just to show how badly Jags cope with this: just search for Nikasil... Start up, move a few feet, Park up and the engine will barely start the next time... My engine has the Nikasil lines and there are in top notch and I only drive my car for at least 10 km... Then the water gauge is at operating level... Oil should be too...

 

I've removed the serpentine belt and the pulley for the power steering pump will turn but it is stiff- is this normal?

In answer, the car has 133,000 miles on it but has had almost everything professionally rebuilt or replaced within the last four years, once piece at a time, so the miles are not a good gauge, maybe.

 

check your PS fluid again. if it has run very low, foaming would
have been present at the time of the refill making for an insufficent
refill.

combined with the later arriving symptoms, the likely culprit is
that the PS pump is on the way out again. when a PS pump is
replaced, all lines must be flushed, a filter installed or the replacement
is a waste of time.

0.25 miles on a bicycle with backpack and panniers is well within
reason and healthy. You don't even have to contend with snow in
Dallas.