Engine won't heat up (1 Viewer)

[Beto Cruiser]

1999 GCC spec Land Cruiser. Having trouble with the heat. The problem is that there isn't any.

I've gone through all the normal steps like making sure the carpet isn't covering the vents, testing both front and rear (neither have heat), etc.

Likely related, the engine temp gauge takes ages to rise up and at best reaches a quarter of the way up. My 2002 LX hits mid range on the guage pretty fast. Figured the thermostat had failed open and that's why I had a cold engine and no heat. I replaced the thermostat, radiator cap, and hoses with toyota OEM today. No change. For fun I tested my old t-stat and it opened at 176 F, so that's about right.

What else could cause this? I can't check for codes (no lights showing anyways). The GCC spec doesn't seem to want to talk to me. It has the OBDII port, but neither techstream nor the devices at auto parts stores can communicate with it.

Thanks in advance!

 

[jLB]

Any chance that a previous owner bypassed the heater core(s) while it was in the Middle East?

 

[jLB]

It has the OBDII port, but neither techstream nor the devices at auto parts stores can communicate with it.

Likely it’s MOBD/M-OBD and not OBD2, if it’s a GCC vehicle. I believe that there are a few threads on here about getting Techstream to work with non-US/non-OBD2 vehicles.

 

[Beto Cruiser]

PO was my father in law. No chance. He said it hadn't worked in a few years.

Likely it’s MOBD/M-OBD and not OBD2, if it’s a GCC vehicle. I believe that there are a few threads on here about getting Techstream to work with non-US/non-OBD2 vehicles.

Awesome, thanks for the tip. I'll check it out.

As far as removing heater core, PO is my father in law. Says he always remembers it being cold. I may have found the issue though. This is the VX.R model. From the parts diagrams, only GX and VX GCC models had a relay on the fan. Mine must just be hard wired and always runs. It runs as soon as I start the engine. I'm going to see if I can't add a relay to mine.

 

[jLB]

Maybe I misunderstood your original post, but I was reading it as “have airflow, but no heat at the heater vents, both front and rear”.

If this is accurate, I’d be looking at coolant flow to the heater core(s), whether intentional (bypassing heater core lines) or just lack of use (stuck valve, blockage, or air)

 

[Beto Cruiser]

I do have air flow. But no heat. And engine dial doesn't reach very high. So that's why I think they may be related. Once the engine dial gets to around 1/4 I feel a little heat from the vents, but not much and it never goes above 1/4 of the way up the dial. So I feel like I'm getting the heat from the flow of the coolant, but the coolant just doesn't get very hot because it's being cooled sufficiently by the fan blowing that cool ambient air.

 

[jLB]

Again, if I’m reading your OP correctly, the thermostat isn’t stuck open, and it opens at ~176* (F).

If airflow through the heater core, with 176* coolant, is lukewarm, obstructed coolant flow to heater, or obstructed airflow through the heater core is much more likely.

As it is non-OBD2, getting an actual coolant number could be a little more difficult than just using a scangauge or torque. Getting Techstream up and running might make it easier to prove/disprove your theory on the cause. Another workaround might be an infrared thermometer, they seem to be everywhere since the coronapocalypse, and try to get a reading from the radiator.

From one of your previous post, it sounded like the GCC cruiser was going to Canada, are you troubleshooting this in Canada or Texas?

 

[Beto Cruiser]

Right, t-stat isn't stuck open. So either something blocking the heater core or the coolant isn't very hot. Wouldn't be hot if the fan is always running, right? I'll try to check with an IR gun when I go to work this week. We have a few.

As far as where it lives, yes, it was going to Canada, and it did, but then it came to Houston! Lucky me (and just in time since my Wife's car was stolen in December). I can't import it (easily) until it's 25, so in the meantime I'll just run it up to Canada once a year to keep it kosher. Living it Houston will at least save it from the salt. Plus not having heat in a Canadian winter is.. yikes.

 

[TXSunDevil]

Is the blend door motor working

 

[jLB]

As far as where it lives, yes, it was going to Canada, and it did, but then it came to Houston!

Well, I might get a chance to see it then!

 

[Beto Cruiser]

Is the blend door motor working

I think so. When I adjust the temperature dial I hear it moving and can feel the difference.

Well, I might get a chance to see it then!

If you see a green cruiser near the med center or midtown with a cheeky emblem poking up on the hood and the GCC stripes on the side, that’s probably it! Might also see the green machine’s younger brother driving around that area too. 02 LX painted blue and with a big roo bar from Ironman 4x4.

 

[Nightbrew]

Maybe the heater core doesn’t have sufficient coolant to exchange the heat correctly. You might check that coolant is at proper level. You may need to make sure all air is burped from the system. To do this you need to run it with the front of the vehicle above the rear. Ramps or a small hill should do the trick.

 

[Beto Cruiser]

Maybe the heater core doesn’t have sufficient coolant to exchange the heat correctly. You might check that coolant is at proper level. You may need to make sure all air is burped from the system. To do this you need to run it with the front of the vehicle above the rear. Ramps or a small hill should do the trick.

Can’t clear the air if the thermostat never opens though. Engine never heats up. Coolant it full to the brim. Tried burping it after replacing thermostat but it never opened :/

 

[Beto Cruiser]

Okay so still stuck.

Looked at the hoses with an IR camera and saw nothing strange. Everything was cool. The engine just doesn't seem to heat up. I also looked a lot at my LX470 and the fan (engine fan) seems to run just as much as the 1999 Land Cruiser, so I'm not convinced that it's some lack of fan relay on more economy-cruisers.

Maybe this helps. The cruiser doesn't have heater tees. Instead, it has just two hoses running through the firewall, nothing teeing off (is that a trans cooler that it tees too)? Either way, the coolant going into the firewall is the normal coolant temp, so it appears to be flowing fine. I looked up heater core bypasses and it seems that it's only done if you have a heater core leak and don't want to fix it. I have no record of this having a leak (father in law owns in, says he never had a heater core leak. He's owned it since 2007). Also no signs of a bypass. What else could it be? I checked the blower inside the cabin by the air filter and no change. Unplugged and replugged a bunch of connectors like another post said and no change. How is this engine not heating up??

 

[Wadepat2]

I can't help much on this issue but i also have a 99 GCC vxr here in Dubai. Its in shop right now but I'll check the heat when I get it back. My temp gauge gets to 1/4 pretty quick and will go to little under half in extreme heat. Engine bay is always hot. Super loud eng fan cycles on and off regularly. I also dont have heater Ts

Odb2 didn't work for me. I got techstream to work pretty easy and it will show basic sensors but not much. Another interesting thing you can check. You likely don't have O2 sensors or catalytic converters. Just a set of open resonators. Not that it matters to heat , just something I found out recently on mine.

Feel free to PM me anytime ,I've done a lot of work on mine and I live in Dubai but fly back home(Louisiana) few times a year through Houston. If you get in a bind maybe I can drop you a GCC specific part. I buy parts often here.

Will be following to see what you find on heat.

 

[aboisvert]

Any update on this? I am considering getting a GCC 100 but I live in Maine and I need heat. I saw a post by someone else that said the size of the heater core is actually smaller on the GCC vehicles. Did you ever figure out the issue? Do you think GCC can provide heat for cold climates?

 

[Beto Cruiser]

Any update on this? I am considering getting a GCC 100 but I live in Maine and I need heat. I saw a post by someone else that said the size of the heater core is actually smaller on the GCC vehicles. Did you ever figure out the issue? Do you think GCC can provide heat for cold climates?

No progress. Other things came up so I let it go. When I get time I'll try to get techstream to work another way but for now it's not being used.

From what I've seen people do run them in colder climates. I grew up with GCC models so I love them, but if I didn't live in a place with them I wouldn't go out of my way. They have a lot of really cool, unique features, but they're harder to work with than a US model (ordering parts, manuals, etc).

 

[Lams]

I have a ‘97 FZJ80 GCC VX-R and it doesn’t have a heater control valve.
The setup is a bit different. I’ll take pictures later on.

 

[2001LC]

Engine water temp reads low + no cabin heat = Low coolant level.

I don't know how a GCC is configured. But the USA 100 series 4.7L 2UZ, has coolant running through the entry system always. There is no control valve.

Engine doesn't appear to get hot, or rather gauge show running cool. Faulty temp gauge circuit. Or coolant level below water temperature sensor.

No or low heat from HVAC, in a warmed-up engine. No coolant flow through heater core.

• Which is either some obstruction in/to/from core
• Coolant below level, needed to reach heater core. MOST COMMON.

Top coolant and bleed off air from system:

Note, of must haves:

• Good thermostat (OEM) properly installed jiggle valve at top, which functions as air bleeder.
• A good radiator cap (OEM).
• No obstruction in reservoir hose, its cap and reservoir.
• Reservoir hose must drop straight (must not be curled) to bottom of reservoir. End of hose, must be submerged in coolant during cool down and normal operation. Or it will suck air into coolant system.

While engine cold, fill radiator and reservoir (full mark) with coolant. With radiator cap on temporally, squeezing upper radiator hose help push coolant into air pockets. You can do this again later, after replacing rad cap during warm up.

Once system topped with coolant, while cap off. Run engine to warm up and add more coolant mixture to radiator as you see it draw down. As soon as you see flowing, as seen looking through top of radiator. Fill to neck and replace radiator cap. You cannot remove cap again, or hot coolant will blow out open radiator.

Run engine (short drive if you like) until at normal operating temperature. Bring RPM up to at least 3K for a few minutes. Shut down engine and park until full cool down. About 8 hours. Air, travel to high point. So, park level or even better, with front end higher than rear of vehicle. That way air pockets at top of radiator (high point)

After complete cool down, before OAT (outside air temp) raises. Remove radiator cap and fill radiator to top and add to reservoir full line if needed.

Continue doing this each morning, until one day after no more coolant can be added to radiator.

Note: coolant is very susceptible to heat expansion. As such the reservoir (expansion tank) level changes with temperature. But the radiator should also be full to the very top. Never open the radiator cap when engine hot, as coolant blows out explosively as it’s under pressure due to heat expansion of coolant. Even removing cap, in the morning after OAT begins to climb, if topped, will come out the cap area/neck. Never remove the cap while doing this topping procedure, until full cool down and ready to top. Doing so, system will lose its vacuum created by contraction/cooling coolant.

Tidbit:
Control valves are like turning on and off water valve. The problem with them is: Coolant will sit stagnant long periods in heater core, until heat is called for by opening valve. This caused the core to rot out and valves to freeze-up as ph of coolant changed. In the 1950, 60, 70's we replaced a lot of heater control valves and cores. Especial in warm climate vehicles, where cabin heat rarely used.

 

[diego355]

Not sure about GCC spec cruisers but my $0.2 cents here.
Lots of vehicles from warmer climates don't actually have heater cores as its an unnecessary option, even top trims dont have them, the cold/hot knob its on the HVAC controls but it doesn't have a heater core.
Do your research before purchasing imports. Im from South America and I have experience this first hand