Nissan Titan Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
28 Posts
Discussion Starter #1
About a week ago I started noticing that if I turned the AC or heat on that I would get a faint burning smell under the hood. I left it off most of the time but every once in a while I would turn it on again and get the same result. Yesterday I turned the AC on and it did nothing for a couple of minutes and then I started hearing a squealing sound. I turned the AC off immediately and it stopped. I have an 08 4x4 CC. I changed the drive belt about two weeks ago and the old belt looked good without any signs of wear. So, no problems unless I turn on AC or heat, then burning smell and as of yesterday squealing. I assume that if it was the idle pulley that it would do it all the time but that may not be accurate. Is it possible that the pulley for the AC is going bad?
 

·
Registered
Joined
·
28 Posts
Discussion Starter #2
Has anyone had this experience or know what the solution might be?
 

·
Registered
Joined
·
289 Posts
Does your 2008 have a condenser fan for the A/C? If so check that for sure. The early titans had a faulty design fan motor that took on water and would burn up.

If not then I would be keeping a keen eye on the compressor when it engages and disengage, specifically pay attention to your belt and make sure it does not stop rotating or get hung up.
 

·
Registered
Joined
·
28 Posts
Discussion Starter #4 (Edited)
It does have a condenser fan on it and it appears to be working correctly. I have noticed that it has become louder over time. Is that normal or a sign of its age? Today I started the truck and raised the hood to look for anything unusual and to see if it had the burning smell with the AC turned off. I didn't notice anything so I turned on the AC on and let it run for a few. No burning smell or squealing today. The condenser fan came on after I turned the AC fan on high. I watched the belt as the AC was turned on and off and there doesn't appear to be any hesitation with the belt. The air inside continues to be really cold and there doesn't appear to be any reduction in the fan speed. I'm not sure what is happening but I'd like to find the problem sooner than later. I'll be driving my truck again tonight for a longer time and will test the AC again. Any other suggestions that anyone has would be great. Thanks
 

·
Registered
Joined
·
289 Posts
Well that is good that your condenser fan is still operable.

Check out post #19 on this thread http://www.titantalk.com/forums/titan-general-discussion/96745-condenser-fan-recall-2.html

https://static.nhtsa.gov/odi/rcl/2008/RCONL-08V284-2893.pdf

I would be suspect at the motor being to awful loud. Have you checked the fins in the condenser and radiator to make sure nothing got lodged in there?

I would run the truck and try to pinpoint the burning smell under the hood/in the core support area or where it may be.

I replaced my belt 2 or 3 yrs ago w/ a gatorback belt and the thing was a PITA to get on. Truck developed a squeak on the belts here within the last year. It comes and goes and is intermittent as of now but I suspect it is coming from the tension pulley bearing.
There is a thread on here of just replacing the bearing that I read recently iirc.
 

·
Registered
Joined
·
28 Posts
Discussion Starter #6
Thanks for your help. I just went out to take a look and I didn't see any signs of anything blocking the fan. I just changed to a Gatorback belt three weeks ago. You're right, it was some work for sure. When it did smell the last time I could smell it under the hood and under both front wheel wells. I will continue to monitor and see if I can better pinpoint where the smell is coming from. It appears that it wouldn't be very hard to change the condenser fan.
 

·
Registered
Joined
·
28 Posts
Discussion Starter #8
How can I troubleshoot the compressor clutch?
 

·
Registered
Joined
·
92 Posts
I dont know how to troubleshoot it... but when it goes... it seizes. The compressor runs in the A/C and defrost modes
 

·
Registered
Joined
·
6 Posts
The description in your original post would be consistent with a compressor or compressor clutch bearing going bad. However, if you've only heard the squeal with the ac on then it's typically the bearing in the compressor housing It would have a hot burning smell potentially with a bit of a rubbery smell but possibly not. Best way to troubleshoot it is to take your belt off of the tensioner and give the ac clutch a wiggle and see if you are able to detect any play in the bearing. As for the condenser fan normally if the motor in the fan was going out it would give off an electrical burn smell.
 

·
Registered
Joined
·
28 Posts
Discussion Starter #11
I drove about 260 miles today. Most of the day I didn't get that burning smell while the AC was on. I did once but I wasn't able to pullover to investigate so I just turned the AC off and the smell went away. When I got home I let my truck run for about 15 mins with the AC on but no burning smell. The condenser fan ran most of that time as I had the inside fan on high. There was no burning smell coming from the condenser fan. So, I guess I will pull my drive belt and see if there is any movement in the AC compressor pulley. On a side note, I have only heard the squealing once and it hasn't done it since.
 
  • Like
Reactions: Teoli

·
Registered
Joined
·
289 Posts
I drove about 260 miles today. Most of the day I didn't get that burning smell while the AC was on. I did once but I wasn't able to pullover to investigate so I just turned the AC off and the smell went away. When I got home I let my truck run for about 15 mins with the AC on but no burning smell. The condenser fan ran most of that time as I had the inside fan on high. There was no burning smell coming from the condenser fan. So, I guess I will pull my drive belt and see if there is any movement in the AC compressor pulley. On a side note, I have only heard the squealing once and it hasn't done it since.
Glad to hear you didn't have any failures on the road. I had mentioned above about watching the belts specifically at the A/C compressor when it would engage/disengage is if there was an issue there whether it is seized internally or it is the magnet that holds that clutch that has failed you should notice/hear something when it is operating.

I had put two belts on my parents 2002 Suzuki XL7 last yr that had 13X,XXX miles on it (they had severe cracking on the OE belts probably) another PITA job to do with absolutely no room in there w/ their 2.7 V6. Long story short after getting the one belt out from underneath a pully (tried to have it ride onto the pully with engine rotation but did not get that lucky) and finally being able to start the car and once it idled up and pretty sure something on the heater control was on and all sorts of loud chatter and some squealing started coming in from underneath the hood. Made me feel sick.
I installed them w/what help my dad could provide, He just so happens to be thebest man, mechanic and fabricator (for what he is working on) that I know and look up to. Seeing that I was defeated he was determined to get to an answer, so he got into the electrical circuit that controls the magnet that holds and releases the clutch for the compressor and upon giving it full ground (I think) we could get the chatter to quiet down a lot. Upon test drive with the circuit still tricked in whatever faction he did it started loosing its hold and went right back to the loud squeeling and chattering pig it sounded like after the belt install. The magnet could not retain its hold even when supplied with proper circuit. Seems to be a lot of different parts and layers to the clutch assembly on the compressor and I think he mentioned something about shims possibly too but at any rate it was and still is loud and a noisy MF.

That and I had once replaced a compressor on a dodge dakota when I worked for a guy that was so siezed the owner had thought he seized the engine because the starter wouldn't slip the belts or attempt to start his truck. This one seized from improper maintenance I would suspect. No refrigerant, oil or debris in the system, who knows but she wasn't turning for the life of that starter or battery.

You never did say what type of smell it was, rubber, wires, oil

If it is your A/C compressor I would find local shop with a good A/C reclaim machine have them do the install and service the system. Those machines are slick giving you your refrigerant and oil all at once. I have hear that A/C systems can be real finicky if there is any trace of moisture in the lines, air pockets and so on. I woud take my truck to an a/c guy with a machine so I knew that $300-400 bill on the part is going to be covered by his specialty or him practicing his trade.

From what you have described above I doubt your compressor is going out but I could be very wrong. I would think that if you sat and watched the compressor throwing itself on and off you would of either seen something with your eyes or noticed something audible that stuck out.

How many miles are on your truck again? If you take the time to drop the drive belt I would defiantly be inspecting the tension pully.

Best of luck keep us updated.

I just got my condenser fan in the mail here this week. Plan on installing it once the rain has passed.

From what yo have described if you didn't see any thing suspicious
 
1 - 12 of 12 Posts
Top