SIGforum.com    Main Page  Hop To Forum Categories  The Lounge    Question Re: 2012 Toyota 4Runner Heater
Go
New
Find
Notify
Tools
Reply
  
Question Re: 2012 Toyota 4Runner Heater Login/Join 
Member
Picture of hjs157
posted
Without warning, the heater in my 2012 4Runner (88,000 miles) began taking much longer to produce hot air. Ordinarily the cabin would be toasty within a few miles of driving. Now I'm lucky if I have adequate heat after several miles of driving. Believing it was the thermostat, I took it to the Toyota garage. Upon inspection, the technician determined the air temperature from the vents was 150° which is within factory specs. (Of course, by the time I reached the garage 10 miles/20 minutes away it had finally warmed up.) They claim to have also checked a few other possibilities including the cabin air filter. Since Toyota couldn't (or wouldn't) diagnose the problem, I'm at a loss. I'm reluctant to take it back since they already hit me with an hour of shop labor. What say SIGforum? Thanks for any recommendations.
 
Posts: 3610 | Location: Western PA | Registered: July 20, 2010Reply With QuoteReport This Post
His diet consists of black
coffee, and sarcasm.
Picture of egregore
posted Hide Post
Start with the basics, because you can't assume they did. This may seem obvious, but is there enough coolant in it? If it is low, add as needed, then see if there are any leaks. (One good thing about Toyota's red coolant is that it is easy to spot leaks because it forms a pink crust.) And how long is the engine taking to warm up? The temperature gauge should start to show at least a little within a mile or so of driving, assuming starting from cold. A slightly stuck open or early-opening thermostat will do this. Slow warmup often turns on the engine light and sets code P0128, but not always. A partially clogged heater core is also a possibility, but remote. The hoses leading into and out of it should be about the same temperature.
 
Posts: 29072 | Location: Johnson City, TN | Registered: April 28, 2012Reply With QuoteReport This Post
His diet consists of black
coffee, and sarcasm.
Picture of egregore
posted Hide Post
It has been a month. I'm the only one who's replied to this? Confused Did you find out anything?
 
Posts: 29072 | Location: Johnson City, TN | Registered: April 28, 2012Reply With QuoteReport This Post
Member
posted Hide Post
If you're willing to troubleshoot, I'd find a friend that has a scangauge or other OBD2 scan device. The temp gauge in the cluster is pretty useless, and the reader will give you actual water temp. If your t-stat is leaking, it will behave as you describe, and take a while to warm up.


Peter
 
Posts: 99 | Location: Chesapeake, VA | Registered: September 05, 2012Reply With QuoteReport This Post
10-8
Picture of Apphunter
posted Hide Post
Another simple possibility is that air has been introduced to the cooling system.
 
Posts: 924 | Registered: November 06, 2004Reply With QuoteReport This Post
Member
posted Hide Post
This acting like a failed thermostat. The fail in the open position. Thus it takes a long time to "warm up".

I suggest you open the radiator cap when the vehicle is cold from overnite. If the coolant is already circulating .... replace thermostat.

Andrew



Duty is the sublimest word in the English Language - Gen Robert E Lee.
 
Posts: 869 | Registered: May 01, 2010Reply With QuoteReport This Post
Member
Picture of hjs157
posted Hide Post
quote:
Originally posted by egregore:
It has been a month. I'm the only one who's replied to this? Confused Did you find out anything?


Thank you for the follow up. I actually sold the vehicle. In addition to the heater issue, I was also approaching a major service interval as well as addressing some minor paint/rust concerns. With the deal Toyota offered me on a new 2021 4Runner, it made good sense for me to trade up at this time. Thanks to all who responded.
 
Posts: 3610 | Location: Western PA | Registered: July 20, 2010Reply With QuoteReport This Post
  Powered by Social Strata  
 

SIGforum.com    Main Page  Hop To Forum Categories  The Lounge    Question Re: 2012 Toyota 4Runner Heater

© SIGforum 2024