No heat while sitting idle, any suggestions?

Topics related to Lights, Radio, Stereo, Headunits, Alternators...

Moderator: volvite

weaver
Posts: 43
Joined: Fri Jan 25, 2019 10:21 am
Location: Ohio hole-pit:)

Postby weaver » Thu Feb 07, 2019 8:30 am

Throwing this out there. I've had coolant leaks so small they were'nt obvious, but over time they cause coolant loss. I have experienced leaks that evaporate or blow away before being noticeable. Heater cores can be sneaky bastards for leaking before you smell coolant inside or get that crappy "film" on the windshield. Tracer dye and a UV light light are cheap and easy to find those leaks that make you wanna go nuts! Other than aftermarket stop-leak (Which for me isn't permanent fix, just buys time and can clog passages) I think it would be "cool" if anti-freeze makers put dye and/or some kind of sealant in the coolant to line the inside of system like Pepto. Then they could double the price too!


User avatar
Zen_master
Posts: 276
Joined: Fri Apr 12, 2013 7:42 pm

Postby Zen_master » Tue Mar 05, 2019 3:40 pm

I burped the system. A few air bubbles were evident but I've seen worse. Coolant level appears full. Still running into the no/low heat at idle problem. Fair to say it's a water pump problem at this point? Any other symptoms that would point to this being an issue? The engine does not run hotter than normal, however.

BullDozer
Posts: 165
Joined: Sun Jan 17, 2016 10:27 am
Location: Detroit, Michigan

Postby BullDozer » Tue Mar 05, 2019 7:36 pm

I know you said collant is relatively new, but at this point I would try drain and refill collant.
I had the same issue as you and after drain and refill its better. Not perfect so I will probably do another drain or maybe flush later.
Before doing my drain and refill I would put in nuetral and rev engine at traffic light to keep warm.

User avatar
smj999smj
Site Admin
Posts: 6054
Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Postby smj999smj » Wed Mar 06, 2019 9:34 am

I doubt that it's the water pump. If it was, it would overheat. Also, the VQ water pumps seldom fail and impeller fan corrosion is almost non-existent these days of long-life coolants (assuming somebody doesn't drain the coolant and re-fill with straight water! You said you burped the coolant, but did you do it the way I often recommend?

First, make sure the radiator cap and reservoir caps are in the right place; the reservoir cap has the spring on the bottom and the radiator cap does not. Make sure the coolant is topped off. Coolant in the reservoir should be at least the MAX FILL line. Jack the vehicle up as safely as possible, or drive up on a set of ramps or park on a steep uphill...to get the nose of the vehicle higher up than the tail. Start the engine and set the front and rear heaters to the maximum hot settings. Run the engine at 2000-3000 RPM for at least 10 minutes or until hot air comes out of the heater vents. If you have a thermometer, normal heat output is about 140 degrees F. Once you get heat out of the vents, you can shut the engine off and lower it, if needed. Re-check the coolant level again when the engine is cold. This usually works 95% of the time, assuming the thermostat isn't stuck open. If you've noticed the coolant gauge needle is sitting near the cold side of the gauge while driving, then I would suggest replacing the thermostat. Typically the needle will sit right in the center of the gauge.

User avatar
Zen_master
Posts: 276
Joined: Fri Apr 12, 2013 7:42 pm

Postby Zen_master » Wed Mar 06, 2019 10:22 am

smj999smj wrote:I doubt that it's the water pump. If it was, it would overheat. Also, the VQ water pumps seldom fail and impeller fan corrosion is almost non-existent these days of long-life coolants (assuming somebody doesn't drain the coolant and re-fill with straight water! You said you burped the coolant, but did you do it the way I often recommend?

First, make sure the radiator cap and reservoir caps are in the right place; the reservoir cap has the spring on the bottom and the radiator cap does not. Make sure the coolant is topped off. Coolant in the reservoir should be at least the MAX FILL line. Jack the vehicle up as safely as possible, or drive up on a set of ramps or park on a steep uphill...to get the nose of the vehicle higher up than the tail. Start the engine and set the front and rear heaters to the maximum hot settings. Run the engine at 2000-3000 RPM for at least 10 minutes or until hot air comes out of the heater vents. If you have a thermometer, normal heat output is about 140 degrees F. Once you get heat out of the vents, you can shut the engine off and lower it, if needed. Re-check the coolant level again when the engine is cold. This usually works 95% of the time, assuming the thermostat isn't stuck open. If you've noticed the coolant gauge needle is sitting near the cold side of the gauge while driving, then I would suggest replacing the thermostat. Typically the needle will sit right in the center of the gauge.
Thanks. Ran it with the front heat on 90 degrees but rear zone on medium. The vehicle was not lifted in the nose. Guess I will try again this weekend.

coatseast
Posts: 23
Joined: Wed Feb 20, 2019 4:23 pm

Postby coatseast » Thu Mar 28, 2019 3:05 am

DdI it work? I h dthe exact same problem and this procedure worked for me.

User avatar
underworld1001
Posts: 328
Joined: Sun Nov 27, 2016 9:05 pm
Location: Austin, TX

Postby underworld1001 » Thu Mar 28, 2019 4:29 am

I have poor heater performance when the vehicle is idling as well. I've been reading up on this and have a hunch it could be the auxiliary water pump that's going bad. Not sure what the consensus would be on that. SMJ?

User avatar
smj999smj
Site Admin
Posts: 6054
Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Postby smj999smj » Thu Mar 28, 2019 12:24 pm

underworld1001 wrote:I have poor heater performance when the vehicle is idling as well. I've been reading up on this and have a hunch it could be the auxiliary water pump that's going bad. Not sure what the consensus would be on that. SMJ?
Try the purge method I described and see if it fixes it. If it doesn't, it may be the heater pump that is faulty.

Sandbox2010
Posts: 3
Joined: Tue Apr 25, 2017 1:40 pm
Location: Boston, MA

No heat while sitting idle, any suggestions?

Postby Sandbox2010 » Mon Sep 30, 2019 8:30 am

Hi,

I hope you have solved your problem. I had the same issue. I'd remote start the car, but it wouldn't heat up. After a few burp sessions (they usually work), the problem would come back. Luckily one of the Nissan techs at my local dealer owned a Pathfinder and had this problem himself.

Answer:

O-ring under the radiator cap was rotted and air was slowly getting in the system.

If you've tried everything else, it don't cost much and fixed mine.

Good luck.

User avatar
Zen_master
Posts: 276
Joined: Fri Apr 12, 2013 7:42 pm

Postby Zen_master » Sun Nov 10, 2019 4:42 pm

Check out these videos. There's a little worm gear that can come loose and fail to actuate the heater control valve.

You can place your hands on the coolant hoses on each side of the valve for an indication if it is failing.

Seems to be a pretty common problem on the 5.6L

https://www.youtube.com/watch?v=Zi68CYFuXmk

https://www.youtube.com/watch?v=IKMpPK5nvXQ

https://www.youtube.com/watch?v=UCSw3xqSqpE

User avatar
Zen_master
Posts: 276
Joined: Fri Apr 12, 2013 7:42 pm

Re: No heat while sitting idle, any suggestions?

Postby Zen_master » Thu Dec 23, 2021 6:02 pm

Two years later and this issue is intermittently occuring. Some days are worse than others.

I did check the heater control valve and the worm gear was affixed properly.

To describe the problem, if the heat is turned all the way up to 90 degrees and the blower is on max, it will often be hot when at idle, but there is a noticeable increase in the temperature of the air coming from the vent when the motor is under throttle starting at about 1500RPM. Everything is pretty consistent and unnoticeable driving around town or on the highway. The times it seems the temp decreases is when the vehicle is at a lenghty idle (long traffic signal, drivethrough, waiting on a passenger, etc.).

User avatar
VStar650CL
Posts: 501
Joined: Wed Dec 09, 2020 6:19 pm

Re: No heat while sitting idle, any suggestions?

Postby VStar650CL » Thu Dec 23, 2021 9:00 pm

I've seen instances where the heater cutoff valve jams or dies in a halfway position and causes crappy idle heat along with less-than-perfect cooling on max A/C. The valve's job is only to cut off the heater flow on max A/C, but when it causes a permanent restriction instead of working properly you get reduced flow that shows up most at low engine speeds. See if your valve cuts the flow on max A/C the way it's supposed to. If not, it may be stuck halfway and causing your issue.


Return to “R51 Electrical”