My 89 xjs marelli ignition makes a loud squeal whenever I turn my fan settings to other then off. Doesn’t matter if the temperature is in cold or hot. It use to just squeal for 30secs to a minute on start up and then go away but now it seems to squeal much more often and longer. Has anyone ran into this problem and be able to teach me on how to fix it? Thanks


my a/c and heater seem to work otherwise. Do these descriptions sound like normal operation??
With temperature on low air comes out of center vent, side vent, and footwell cold. Side vents don’t blow as hard as center vent though. Now that I think about it, i don’t think fan speed changes from the side vents when selecting the different options.
With temperature on hot, air blows from the footwell hot. No air coming from center vents. And coldish air, not hot blows from the side vents.
With temperature on hot and fan setting on defrost, air blows to the windshield but doesn’t seem hot at all.

thanks for the help. Only owned this xjs for a couple months now.

 

Here is a video of the said squealing so you guys can hear. Today it was doing a different tone squeal that lasted much longer that got me concerned to post a thread

 

Your air flow sounds right, sortof.

is your heater valve working? Defrost should be scalding hot with all other vents off or low

Jaguar cars always have low fan as medium, high is deafening, "low" might as well be "off"

Never attempted to 'service/lube' the XJS system its abit much but mineral oil in the right spot resolves squeeling it worked on my F350 with its squirrel cage blower.

 

More than likely, if the sound is inside the cabin, the fan blades hitting the fan outer because the bearings are now worn out. The fans can be removed and a new motor sourced (not a Delanaire motor but one that can be made to fit from a Mercedes) and fitted with a bit of fettling

 

I second that. I actually took my squealling LH fan motor apart and shimmed it up to remove excess slack in the quite primitive bearings. I had 3mm axial play, which I reduced to 1mm, using plain washers as shim, so we are talking about big tolerances...

Procedure is described a bit over halfway down this page: Service log 2010 ? present ? XJ-S

 

Does the squeal come from the engine bay? Maybe the air conditioning compressor drive belt could be loose, and the load created by the compressor could be causing this loose belt to slip and squeal?
Does the squeal come from in the cabin under the dashboard? Maybe one of the ventilation blower motors could need oiling or could be wearing out. This happened to me and I removed the motor, lubricated it and reinstalled it and I haven't had any more problems. By the sounds of some of the other replies though, I may have been lucky to stop the squealing this easily.

Regarding the air temperature in the different vents, have you spotted the weird little temperature slider below the radio? I think this is meant to adjust the temperature of the centre vents independently of the other vents. I overlooked it when I first got my XJS and I was similarly confused by the results I was getting.

 

yes it does sound like its coming from inside the cabin. I tried posting a video of it but i guess you can’t attach videos in this forum. Sorry for my lack of knowledge but what fan are you talking about? The mechanical fan or aux elec fan in the engine bays?

 

I am talking about the fans that are in the cabin that blow he air into the cabin through the heater/aircon unit.

 

okay so i see where talking about blower motor fans in the dash. How do I access these blower motor fans to service? Any tutorials?

I have played with the little slider for temperature control, in my xjs it doesn’t seem to do anything. I think maybe when everything it off it might affect the temperature from the center vent. I would have to mess around with it more to verify.

i have a parts catalog and a rom I will try to look into but any help would be appreciated

 

Here’s a link to a video I made a couple days ago with the ac squeal noise present so you guys can hear it

 

Here’s two links I found relevant to the issue I have
Replacing The HVAC Blower Modules.

Air conditioning blower control

 

Here is some more info. I verified both blower motors work by pulling each fuse. With the engine off and cycling through the fan speeds there was NO squeal. With the engine on the squeal was present, it was not coming from the engine department and was more in the cabin area or might even be coming from under the wiper motor grill. Any advice? I'm not sure if its the blower motor making the noise because it didn't squeal when the engine was off and the motors on. Want to get some more opinions before I decide to mess with the blower motors.

I can't seem to find my heater valve in my engine bay

 

I can see the video now.
To me, it sounds like the noise must be coming from one of the two blower motors in the cabin. I see you've also found some guides on how to replace them. =)
You've got to decide how rich you're feeling vs how much time you have. Do you....

1. identify which one of the two motors is noisy, take it out, lubricate it and reinstall it (might not help for long)
2. take it out and try to rebuild it
3. take both motors out and try to rebuild both of them
4. take both motors out and replace them with new/rebuilt units
5. pay a specialist to do this for you

Incidentally I noticed on your video that your battery voltage gauge is only showing about 11 volts. In a normal car, that would indicate a problem with the alternator and you'd be heading for trouble. In an XJ-S it probably indicates bad connections in the instrument cluster. I followed some online advice to take my instrument cluster apart and sort it out, and now the gauge reads correctly. The same low reading issue can affect the other minor gauges (temp, fuel, oil pressure).

 

You're taking a good approach... In my experience the blower motors only squealed when they were cold and hadn't been used for a while. Perhaps the squealing may also only occur when the engine is running because the alternator will be generating a higher voltage to the blower motors, making them spin faster? You'll probably hear this squealing in the vicinity of the wiper motor grille because the blower motors draw air in through that grille, meaning the squealing sound can pass out through it.
However, there might be some other possible cause for the squealing that I'm not aware of.

 

Makes sense, I'll put the blower motors on my to-do list. Might be able to get to it next week hopefully. Has anyone been able to watch my youtube video of the noise in the above post? My gut feeling points to the blower motors like everyone is saying but I guess im just trying to avoid having to tear into it.

 

Yes, I was able to see your video the second time you attempted to post it. I wrote a reply but that reply went into limbo - I think my posts require approval because I'm a new user?
Anyway, the behaviour of the squealing in the video seems more like a blower motor squeal to me.
I also noticed your battery voltage gauge is reading low (~11V instead of ~14V). That's probably caused by bad connections inside the instrument cluster, and there are guides out there about how to fix this too. =)

 

thanks for the help. Yes the video I made was originally made because of the low voltage reading. Really wonky, sometimes it reads right at 13 volts. Sometimes at 11. And sometimes even below that into the red. Had a couple times the gauge doesn’t even move from the bottom of the red. But I have checked my battery when the engine is running and it’s always >13.25 volts. And the battery is only a couple months old. And I’ve had the car sit for two weeks or so and it will still start. What’s weird is when there car sits for a week it will start and voltage will read right at 13 in the middle. But with daily driving it usually sits at what you see in the video 11volts touching the red. I will try to search for the guides your referring too

 

There may be multiple guides, but one of them is a pdf called "Experience in a Book: Help for the Jaguar XJ-S Owner" by Kirby Palm.
Here's the intro to the relevant part: