Anyone else's T4R hate the heat?
- Thread starter vondy21
- Start date
borfoo3
New member
I live in the hottest spot on earth. The 4runner does fine even in the midst of summer. I had more issues with the programmed sluggish pedal feel vs heat power losses but mods helped out. I run with better fuel and an aux fan to help the AC.
My other car is a turbo Subaru, and THAT thing suffers badly with heatsoak during summers vs the 4Runner
My other car is a turbo Subaru, and THAT thing suffers badly with heatsoak during summers vs the 4Runner
LandCruiser
New member
Not a fan of high elevations and 100 degree weather.
progress4m
Member
TO OP: I am in DFW area as well, no issue with my truck… of course AC is on all the time and high temp does effect overall performance (as expected), but nothing even remotely to what you described… something is off.
RocketCowboy
New member
I picked up my new 18 Limited right before DFW had our recent string of record setting heat. Can't say I noticed anything on those days compared to this week when the temps have been down to just the upper 90s. She still has less than 500 miles on the engine, but has been handling anything I've thrown at her without a complaint.
vondy21
New member
I might try out some 93 octane next time I fill up and see if that makes a difference.
I know Toyota builds their vehicles to run all over the word, including in extreme environments, which is why I was surprised when mine was having trouble in the Texas heat. Perhaps 110 degree, slow moving, downtown traffic is the most extreme environment.
Rapid_Amble
New member
I haven't noticed anything unusual related to performance this summer.
ScoMey
New member
Three words... thermostatic clutch fan
Here's an entirely different perspective nobody has brought up...
... Our 4Runner's are all equipped with thermostatically controlled clutch cooling fans. Those fans, when fully engaged (i.e., when it's hot out, especially when starting from a stop) take A LOT of horsepower to turn... which is why they have temperature controlled clutch mechanisms to disengage them once there's sufficient air moving across the radiator and/or A/C condensers. Once you're up to speed and moving, the fan clutch loosens up (lack of a better way to put it) reducing the HP drag on the engine.
In the past, thermo clutch fans were often part of high performance engine options from Detroit for this exact reason... at slow speeds or when the car was stopped in traffic, the fan engaged to pull more air in through the radiator... once up to speed, the fan would disengage... freeing up more horsepower.
I've experienced the same feeling of low power in really hot conditions... and I've always also noticed way more engine fan noise (fan fully engaged) when that's happening. Coincidence?
Here's an entirely different perspective nobody has brought up...
... Our 4Runner's are all equipped with thermostatically controlled clutch cooling fans. Those fans, when fully engaged (i.e., when it's hot out, especially when starting from a stop) take A LOT of horsepower to turn... which is why they have temperature controlled clutch mechanisms to disengage them once there's sufficient air moving across the radiator and/or A/C condensers. Once you're up to speed and moving, the fan clutch loosens up (lack of a better way to put it) reducing the HP drag on the engine.
In the past, thermo clutch fans were often part of high performance engine options from Detroit for this exact reason... at slow speeds or when the car was stopped in traffic, the fan engaged to pull more air in through the radiator... once up to speed, the fan would disengage... freeing up more horsepower.
I've experienced the same feeling of low power in really hot conditions... and I've always also noticed way more engine fan noise (fan fully engaged) when that's happening. Coincidence?
Ron4RNevada
New member
No PROBLEM HERE
In the norther Nevada boonies.
This July has set an all time record for JULY -> 16 days over 100 degrees. However I'm not in a large city with traffic - our rush hour lasts from 11:55 t0 12:05 (everybody going to lunch). Also our relative humidity is about 9%.
rush hour
In the norther Nevada boonies.
This July has set an all time record for JULY -> 16 days over 100 degrees. However I'm not in a large city with traffic - our rush hour lasts from 11:55 t0 12:05 (everybody going to lunch). Also our relative humidity is about 9%.
rush hour
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vondy21
New member
Yeah we had 15 days 100+ in July with an average humidity of around 60%.
You know it's been hot when the temps are in the upper 80's and you comment on how nice it feels outside.
Thats a good point. We drove from Portland to central Oregon last week over Mt Hood - so elevation and it was 97 out. I was wondering why the engine was noticeably louder even when stopped at the top of the pass to let the kids out.
83Mule
New member
We are on our 68th day over 100 this year....and will not drop until late september probably. No driveability problems here. I HAVE had issues with my Express van acting gutless and it has been Traction Control related rather than heat. Do our 4runners have a way to defeat traction and stability control? I can over-ride it on the Van by holding a button down in park.
I think you just nailed it. It's probably (avoiding) detonation on a hot engine with hot intake air.
I think when you're saying it disengages at speed, you mean road speed? Reality is they disengage at a certain engine speed as well. You can hear the fan and the drop in power is noticeable but I don't think that's it. OP is describing a near-"oh my god why am I not even moving" thing for 2-3 seconds, where the truck feels like its trying to take off in 5th gear in 4wd towing a trailer. And then you feel like "that jackass" because it caused you to pull out in front of someone without accelerating.
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Jevans1770
New member
What's your aux fan setup? My AC takes forever to cool things down when its above 90F.
borfoo3
New member
http://www.toyota-4runner.org/5th-gen-t4rs/218460-5th-gen-auxiliary-fan.html#post2442167
My last post has pics. Basically the fan from a Prado (or any fan) and a relay wired to run when the AC compressor is on.
83Mule
New member
The intake air temp goes high, the sensor tries to keep the mixture correct with the thin hot air and pulls fuel so you will lose power. I think where the 5th gen pulls air from is a crappy spot full of heat and dirt. I made a cowl induction for my PU and it helped both heat and dirt ingestion. I wonder if a Snorkel or cowl induction would cure this on the 4Runner.
CookieJHWK20
New member
Maybe look into some different oil or a higher octane of gas. I will alternate between 93 octane and 87 in my '03 4th gen and there is a significant improvement in speed and engine quality with the higher 93 octane gas.
