ScanGauge Temp Reading (1 Viewer)

[Dirt J]

What does your SC show, once at operating temp, at idle and cruising?

Mine says "WT" which I assumes means water (coolant) temp?

I'm running 215 or so at idle with AC on. Ambient 72. Lower while cruising.

 

[shane431]

I’m at 184-186. During TX summers I’ll get up to 194-196. 215 is too high!

 

[Dirt J]

That's on a Scan Gauge?

 

[Trunk Monkey]

190ish.

 

[shane431]

That's on a Scan Gauge?

Yep! I think your temps are too high unless you’re going up a steep grade or towing heavy accelerating hard.

 

[Dirt J]

I have a pulley with a bad bearing I need to replace, so I'll try that first before looking at fan clutch.

 

[Import Driver]

Do the temps drop once you start moving?

 

[Dirt J]

Yes

 

[TRDdrew]

Idles at 186-188 max 191 while driving

 

[Hokie LX]

On my scangauge I sit around 185-190 this time of year. 195 during the hot summers. Rarely if ever 200+ when towing

 

[Dirt J]

Thanks guys. I guess my fan clutch is going. Will get on that!

 

[2001LC]

Radiator fins need cleaning! Alert Alert Alert

I've a 06LC w/192K I just bought. In reading history I found PO complained of engine temp raising when both front and rear AC on. Toyota Dealership diagnosed with clogged radiator fins. Recommended new OEM radiator, $600 for the US spec Radaitor plus coolant and labor. They should have added...

forum.ih8mud.com

 

[Dirt J]

Radiator fins need cleaning! Alert Alert Alert

I've a 06LC w/192K I just bought. In reading history I found PO complained of engine temp raising when both front and rear AC on. Toyota Dealership diagnosed with clogged radiator fins. Recommended new OEM radiator, $600 for the US spec Radaitor plus coolant and labor. They should have added...

forum.ih8mud.com

That would be worth my time to try. Thanks!

 

[89BIGBLUE]

That would be worth my time to try. Thanks!

It makes a surprising difference!

 

[Mchodl]

181-186 all oem parts

 

[devilzdriver]

Its been pretty cold around here (30~40's) cruising at 70~ I sit at about 186~188. Sitting at a light or heavy traffic highest I see is around 193~.

 

[Dirt J]

Did some further investigation:

Tried the rolled-up-magaizne-in-fan test, and it did not seem to faze it. This was done at operating temp. So I think fan clutch/clutch fluid is still good.

Checked coolant level, once cool, and found the overflow reservoir totally empty and the radiator about 1/2 gallon low. Topped off both.

So then question became: where did the coolant go??

Checked oil level (with fingers crossed) and it was at about the 1/2 point of the hashmarks. Going on 6k for this oil change, so about time to change. Would have expected watery and high oil level if leaking into oil.

Consulted with my more mechanically inclined BIL and told him there was no leaks under the bottom...only the A/C condenser drainage. But now that I'm looking at it, there's a lot of condensation drainage under it and it looks kinda red and oily...

So we think we found the culprit: heater core. Specifically heater core leaking into the HVAC housing under the dash and draining out the drain tube.

We are going to pressure test to confirm and also more visual checks to ensure that fluid is indeed coming from the drain tube and not *near* the drain.

If confirmed, I'll round up a new heater core and probably a radiator while I'm at it.

Planning to install the new fan clutch that's on the way, since mine is OE and has 337k on it.

If confirmed, until the new parts get here, I think I'll bypass the core at the firewall to avoid continued coolant loss.

Highway and stop-go traffic this morning just had me no higher than 193 this morning. 55 ambient. Amazing what the proper amount of coolant will do!

 

[rexington14]

With the truck running look underneath the front of the engine for dripping (water pump leaking)

 

[Dirt J]

No drip there and pump is not very old. Did a timing belt not too long ago. But good to check! Thanks!

 

[2001LC]

I find a difference in 00-02 compared to 06-07.
ECT 00-02 184F to 187F all day long up a downs mountains HWY, light off road after 6 hours or so then city HWY stop (I mean stop) and go at with 100F fully 3PM sun on asphalt. Both A/C on full high. I'll hit 190F for a moment as I stop, then back down to 187F.

06-07, on days OAT above 68F, I see 194 to 197F. With stops hitting ~199F momentarily before backing down to 197F (same conditions as above).

I need to also run some test one day on 98-99 and 03-05.

Two major differences.
A/C condenser fan. in all 00-02, some 98-99, no 03-07.
06-07 different fan clutch and fan blades.

Did some further investigation:

Tried the rolled-up-magaizne-in-fan test, and it did not seem to faze it. This was done at operating temp. So I think fan clutch/clutch fluid is still good.

At cold start, can not stop fan blades (clutch) for ~2 minutes.
Then fan blades can be stopped, through warm up in to hot ECT
Then fan blades can't be stopped. As ECT above ~187F. Radiant heat from radiator, heats and expands coil on fan/fluid clutch face. Fluid in fluid clutch moves to lock clutch/fan blades.

Checked coolant level, once cool, and found the overflow reservoir totally empty and the radiator about 1/2 gallon low. Topped off both.

So then question became: where did the coolant go??

Most times it was not brupped properly, last time coolant drain/flushed. But be sure to hunt for leak.

Checked oil level (with fingers crossed) and it was at about the 1/2 point of the hashmarks. Going on 6k for this oil change, so about time to change. Would have expected watery and high oil level if leaking into oil.

Oil is check 15 minutes after hot (op temp) engine shut down on level ground. If set to high mark, when OF&L service done last. Will still be at high mark 5K miles later.

Consulted with my more mechanically inclined BIL and told him there was no leaks under the bottom...only the A/C condenser drainage. But now that I'm looking at it, there's a lot of condensation drainage under it and it looks kinda red and oily...

So we think we found the culprit: heater core. Specifically heater core leaking into the HVAC housing under the dash and draining out the drain tube.

A/C condenser should drain clear. If red from coolant, it would not be oily.

The power steering reservoir (use red ATF) and hose are in same area. You may be seeing mix, form two separate areas.

Careful here. I've seen perfect fine heater core called bad.

We are going to pressure test to confirm and also more visual checks to ensure that fluid is indeed coming from the drain tube and not *near* the drain.

Good idea.

If confirmed, I'll round up a new heater core and probably a radiator while I'm at it.

Planning to install the new fan clutch that's on the way, since mine is OE and has 337k on it.

If need for sure. Not being able to stop fluid clutch (fan blades) ~2 minutes after cold start or as engine warms up to ~187F. Is a bad fluid clutch. These will usually not spin or very hard to spin even when engine off and cold, warm or hot.

If confirmed, until the new parts get here, I think I'll bypass the core at the firewall to avoid continued coolant loss.

Heater cores very rarely fail in 100 series. Unless improperly maintain coolant system. i.e. using other than distilled water (DW) (98-03 Toy LL red 100%, mix with red/DW 50/50) in coolant system. No water should be add to 04-07 (Toy SSL pink pre mix). Failure to flush system and then park vehicle for extended period of years.

Highway and stop-go traffic this morning just had me no higher than 193 this morning. 55 ambient. Amazing what the proper amount of coolant will do!