Notices
General Miata Chat A place to talk about anything Miata

Weak a/c and heater

Thread Tools
 
Search this Thread
 
Old Apr 12, 2012 | 03:56 PM
  #1  
Braineack's Avatar
Thread Starter
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default Weak a/c and heater

Worked fine when I left the car in Oct.

Dad complained that the a/c wasnt working well a couple weeks ago, I called him silly.

Now that I'm driving the car again, I can say, yes, the a/c doesn't blow cold...but the compressor is engaging.

But, on top of that, the heater isn't blowing very warm at all.


I did a quick poke up under the dash and it appears all the ***** and pulleys are working, and if I do change from warm/cold or the different vents there is change in temp/flow.

But I have noticed that when i set it to floor, it will still come out quite heavily out the main vents.

Think I developed some sort of leak in the system somewhere?


My feets are cold the morning!!!! I don't see how I can possibly have low heater temps when the coolant is getting up to 180°F
Old Apr 12, 2012 | 05:04 PM
  #2  
rleete's Avatar
Elite Member
iTrader: (21)
 
Joined: Jun 2007
Posts: 6,794
Total Cats: 1,342
From: Rochester, NY
Default

Vacuum line disconnected/broken?
Old Apr 12, 2012 | 05:30 PM
  #3  
Braineack's Avatar
Thread Starter
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

vacuum line to what?
Old Apr 12, 2012 | 06:38 PM
  #4  
rleete's Avatar
Elite Member
iTrader: (21)
 
Joined: Jun 2007
Posts: 6,794
Total Cats: 1,342
From: Rochester, NY
Default

Sorry, my bad. I thought the selector was vacuum powered, but I'm mistaken.
Old Apr 12, 2012 | 07:57 PM
  #5  
thegrapist's Avatar
Junior Member
 
Joined: Jun 2010
Posts: 153
Total Cats: 3
From: Mid-Atlantic
Default

I don't know if the NA's have the same setup as the NB's. But check the cables coming from the hvac controls along both sides of the trans tunnel. I had a similar problem when I pulled my dash and put it back together (badly). There's a billion flaps that block the heater core on the driver's side and on the passenger side they adjust the air flow. Sometimes the levers that are connected to the cables get jacked up and needs to be manually moved around.

Check the link for pictures and a better explanation of what's going on:

http://www.miata.net/garage/heater_cable.html
Old Apr 12, 2012 | 09:16 PM
  #6  
olderguy's Avatar
AFM Crusader
iTrader: (19)
 
Joined: Oct 2004
Posts: 4,716
Total Cats: 364
From: Wayne, NJ
Default

Originally Posted by thegrapist
I don't know if the NA's have the same setup as the NB's. But check the cables coming from the hvac controls along both sides of the trans tunnel. I had a similar problem when I pulled my dash and put it back together (badly). There's a billion flaps that block the heater core on the driver's side and on the passenger side they adjust the air flow. Sometimes the levers that are connected to the cables get jacked up and needs to be manually moved around.

Check the link for pictures and a better explanation of what's going on:

http://www.miata.net/garage/heater_cable.html
Good idea, since Scott DID have his apart
Old Apr 24, 2012 | 11:17 AM
  #7  
Braineack's Avatar
Thread Starter
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

I'm pretty sure all the flappers are working, but ill double check.

it was working for sure in Oct when I left the car with my Dad for winter. He complained and when I picked it back up in March it wasn't working well for sure.

I can move from hot to cold, and there is a bit of a difference. Recirc/outside works, I've verified that. I have noticed that when i move it to feet only it blows out of the main vents still, that's not normal.

the heater is barely getting warm, maybe blowing 60°F, well after the car reaches 170°F. The a/c is nonexisitent but the compressor is engaging.
Old Apr 24, 2012 | 11:22 AM
  #8  
Reverant's Avatar
Elite Member
iTrader: (10)
 
Joined: Jun 2006
Posts: 6,020
Total Cats: 369
From: Athens, Greece
Default

Two plane tickets, a couch to sleep and your problem is as good as solved.
Old Apr 24, 2012 | 11:26 AM
  #9  
Braineack's Avatar
Thread Starter
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

I have a really huge couch too, sleeps two confortably (if you spoon) and tends to be full of kitties.
Old Apr 24, 2012 | 11:37 AM
  #10  
MD323's Avatar
Junior Member
 
Joined: Sep 2010
Posts: 369
Total Cats: 3
From: SFL
Default

i dont know if the miatas suffer the same issue as the FWD cars, but when our cars do the same thing, its usually debris in the air intake in the cowl area.
Old Apr 24, 2012 | 02:09 PM
  #11  
olderguy's Avatar
AFM Crusader
iTrader: (19)
 
Joined: Oct 2004
Posts: 4,716
Total Cats: 364
From: Wayne, NJ
Default

Mouse nest
Old Apr 24, 2012 | 02:10 PM
  #12  
Braineack's Avatar
Thread Starter
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

didn't think of checking that. will do. blower blows at full steam, its just always pretty much ambient.
Old Apr 24, 2012 | 08:01 PM
  #13  
ssmith's Avatar
Junior Member
iTrader: (10)
 
Joined: May 2008
Posts: 149
Total Cats: 6
From: Baldwin Park, CA
Default

Just found the same problem with my heater, no ac. Brand new blower, blows hard, but never very hot. Engine temp hangs around 195.
Old Apr 24, 2012 | 08:06 PM
  #14  
MD323's Avatar
Junior Member
 
Joined: Sep 2010
Posts: 369
Total Cats: 3
From: SFL
Default

Originally Posted by Braineack
didn't think of checking that. will do. blower blows at full steam, its just always pretty much ambient.
yeah the system isnt airtight (again in the 323) so when it cant pull air in from the vent and acrossed the heater/condesner assembly it pulls it thru every crack and opening in the system.
Old Apr 24, 2012 | 08:12 PM
  #15  
rleete's Avatar
Elite Member
iTrader: (21)
 
Joined: Jun 2007
Posts: 6,794
Total Cats: 1,342
From: Rochester, NY
Default

So, you're saying Brain has excessive air flowing through his crack?
Old Apr 24, 2012 | 09:09 PM
  #16  
adamvanxxx's Avatar
Junior Member
 
Joined: Mar 2011
Posts: 76
Total Cats: 1
From: Indianapolis
Default

There are 3 cables check them all, also are the clamps for the big black A/C (Don't know what it really is) box still clamped? Mine had rattled loose once.
Old Apr 24, 2012 | 10:10 PM
  #17  
MD323's Avatar
Junior Member
 
Joined: Sep 2010
Posts: 369
Total Cats: 3
From: SFL
Default

Originally Posted by rleete
So, you're saying Brain has excessive air flowing through his crack?
No but id like to change it to that
Old Apr 26, 2012 | 07:15 AM
  #18  
skidude's Avatar
Elite Member
iTrader: (3)
 
Joined: Apr 2008
Posts: 2,023
Total Cats: 19
From: Outside Portland Maine
Default

My vote is for a mouse house somewhere preventing a flap or two from moving. Stupid mice need to die in a fire.
Old Apr 26, 2012 | 08:50 AM
  #19  
hornetball's Avatar
Elite Member
iTrader: (4)
 
Joined: Mar 2008
Posts: 6,301
Total Cats: 697
From: Granbury, TX
Default

I thought Brain had kitties to take care of mice?
Old Apr 26, 2012 | 08:59 AM
  #20  
Braineack's Avatar
Thread Starter
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

I was up under the dash yesterday. All the sliders have full articulation at the flappers.

the hot/cold will change from just below ambient (with a/c acitvated) to luke warm (with heater). Viewed from right side of center console.

I can watch the recirc slider open the flapper at the blower motor in order to source air from behind the glove box or up through the intake vent.

All the vent positions change. Viewed from right side of center console, verified flow with my face/hand.

so unless there's something else in the box behind the center console that might be stuck/blocked I dont quite see what the dealio could be.


The heater core inlet is hot as ---- and scolds me if it touch it. I can bare a few second on the outlet...so that makes me think the core isn't blocked.



All times are GMT -4. The time now is 03:47 PM.