Hey just a couple of unrelated questions about the x300,

1-when going along at speed in cold weather I notice a cool air coming from under the steering column about knee height, I’ve had this on both x300’s I’ve had but just wondered if this is normal?

2-the car is unfortunately normally parked outside, after driving a short while I notice there is a small amount of condensation inside the dash instrument display, on the inside of the plastic screen behind the steering wheel, is this normal on a car kept outside or will it eventually lead to electrical issues?

and finally

3- after driving about 30 miles earlier, i parked up and lifted the bonnet, i touched the plastic where the tool kit is (exhaust manifold side of engine) and it felt really hot, not melting hot but you wouldn’t want to hold your hand there all day! Is this normal to be that hot, I did have a crack on a down pipe repaired a while back and the manifolds have been replaced so definitely not them!? It may well have always been getting that hot and I’ve just never touched it, any ideas?

thanks for any help!

 

1) I havent noticed a draught.
2) Mine sits out most of the time, and I have never had any misting inside the instrument pack. It would I suspect take a fair amount of time to lead to electrical issues from condensation, but it might be suggesting that water is getting into the car somewhere, and that is definitely worth checking out. Unhelpfully, the carpets are rubber/ plastic backed, and so can be dry to the touch, but wet underneath allowing water to sit on the floor pan. The front outside corners of the front floor pans would be a good place to check first, most particularly if your car has a sunroof.
3) If you were in a lot of stop start traffic, it could become warm, but not burning hot. The material it is made of would have limited tolerance to excessive heat cycles. Was the exhaust heat shield put back on when your manifolds were repaired?

 

My 97 has been the most reliable car I ever owned. Oil consumption super low, no coolant leaks ever, nothing broken. The only gremlin is some front brake shudder slowing from high speeds.

 

Hi Jagguyx300,

This is not normal. The blower motor housings connect to rectangular holes under the windshield cowl that allow fresh air to enter the cabin unless the recirculation mode is selected, when flaps move to cover the openings and block outside air. The blower motor housings are sealed to the opening in the body with a weatherstrip gasket. You can see the rectangular hole in the top of the blower housing in this diagram:




The blower motor housings connect to the Air Conditioning Control Module (A/CCM) via plastic ducts. The ducts deform and lose their seal and allow air from the blower motor housings to escape into the footwells directly instead of flowing into the A/CCM. When this happens, the portion of outside air that leaks out of the ducts does not pass through the heater core. Here's a diagram that shows what the ducts/pipes look like:




An easy way to test if your ducts are leaking would be to turn the fans to a low setting but not off, and press the recirculation button on the climate control panel. If you press and release the recirc button, recirculation will remain on for 5 minutes. If you press and hold the recirc button for 2 seconds, recirculation will remain on until turned off.

If the cold air on your knees stops with the system in recirculation mode, your ducts are probably leaking. You can probably seal the joints with duct tape. Your primary concern will be the ducts that connect the blower motor housings to the A/CCM, but you may improve the air flow from your fans by sealing every duct joint you can access.

Cheers,

Don

 

Don, I want to thank you personally for this little tidbit of information. You have quite possibly answered my occasional problem with my heater.

 

My first suspicion would be that the drain under the air conditioning evaporator in the A/C Control Module are clogged with deteriorated insulation, and water is pooling in the tray under the evaporator and causing high humidity under your instrument cluster. The drain tube, Part 5 in the diagram below, connects to the evaporator tray and directs condensation down through the side of the transmission tunnel so it can drip out under the car:

Other possibilities might include a leaking windshield seal, or a disconnected or kinked sunroof drain in the A-pillar, causing rainwater to drip down into the dash.

Cheers,

Don

 

It's normal for the exhaust manifold side of the engine bay to be hot, but it would be worth checking your catalytic converter in the dark after a long drive to see if it is glowing red. If so, the cat is partially clogged, the fuel injectors are leaking, or some other malfunction exists.

Cheers,

Don

 

Thankyou very much for such informative answers! As for point 2, the aircon doesn’t work on my car unfortunately so could a pool under the evaporator still be a possibility? The windscreen was recently replaced but I had the issue previous to that and there is no sunroof?

 

Don, As you said when I put it into recirculating mode the cold air on my knees disappears, how do I access the ducts so that I can duct tape them? Thankyou very much!

 

Hi Jagguyx300,

To access the ducts, you have to remove the knee bolsters/underscuttles and you may have to remove or displace other components. The underscuttles are attached with a couple of screws and fir tree press fasteners:



Cheers,

Don

 

Thankyou, my aircon doesn’t work and hasn’t for ages so could this be the cause?
im planning on getting the aircon fixed so how can I make sure this drain is clear of insulation?

 

Hi Jagguyx300,

Clogged drains will not prevent the A/C system from working, though an accumulation of deteriorated foam insulation collected on the evaporator could reduce its heat transfer efficiency and reduced cooling in the passenger compartment.

Likely causes of inoperative A/C include low refrigerant (usually due to one or more leaks), a failed compressor clutch or clutch electrical circuit, a failed compressor, a failed pressure switch, failed control module, or other issues. Diagnosing the malfunction requires a manifold gauge set and a good understanding of the system operation and proper safe test methods. Working on an A/C system is potentially dangerous, so my recommendation would be to have it inspected by a good automotive A/C specialist.

Cheers,

Don

 

Thankyou! My compressor was jammed when I bought the car 5 years ago so I just removed the aircon belt as couldn’t afford to fix it then but now I really want to start doing the car up, it’s future depends on having aircon as it’s unusable in summer without it.
So far I’ve got a good second hand compressor and expect I need the following.
receiver(dryer)
condenser.
plus other bits you’ve mentioned!?

i don’t plan on doing anything myself, I have a choice of a recommended aircon specialist a couple hours away or a guy who used to work at a jag dealer about 20 years ago nearby.

I don’t know what a manifold gauge set is unfortunately but hopefully one of my above mechanics has a clue about this system!

im just concerned the evaporator might be broken as I know that is a dash out job which I can’t afford. Would a good aircon place be able to diagnose this?
Thankyou for your help!!

 

Yes, a good A/C shop can diagnose evaporator leaks, but there's a good chance that the seized compressor was your primary problem.

Please keep us informed!

Cheers,

Don