EGT's on the 1GD

[Prado_Joe Lurker Find all posts View Profile Close Prado_Joe]

Because I tow a 2T van, decided to invest in a Scangauge to monitor EGT and auto fluid temps. Now I have seen EGTs of 550+ on my Scangauge locked up in 4th towing a 2T van up long hills using a fair bit of right foot. Thats starting at the bottom at 110km/hr and progressively dropping to ~ 90km/hr at the top.

I thought this was quite good, leaving a pretty decent margin before things got too hot. Learn't the other day however that Mr Toyota in his wisdom put the EGT sensor (Bank 1, Sensor 1) on the far side/after the turbo. Now I'm thinking that 550 probably corresponded to a genuine EGT more like 650-700C which is way too hot for my liking.

Does anyone know if it's possible to insert an additional probe pre-turbo on the 1GD ?

[watsea Member Find all posts View Profile Close watsea]

Hi Joe,
I have been monitoring EGT while I am towing using the TorquePro app. There are four sensors built into TorquePro for display- Bank 1, Sensors 1 to 4. I do not know where the sensors are.
I simply chose Bank 1, Sensor 1. After reading your post, I will add the other Sensors to my screen to see what I can read. The screen is getting rather cluttered with displays.

[Prado_Joe Lurker Find all posts View Profile Close Prado_Joe]

The only diagrams I have seen is the ones here: https://toyota-club.net/files/faq/15...engine_eng.htm

Shows 3 temp sensors: Sensor 1 between Turbo and CAT, Sensor 2 between CAT & DPF and Sensor 3 downstream of DPF.

(Can't seem to upload an image without getting a "Your sessions timed out while you were operating and you were logged out." hence URL)

I'm reading sensor 1 ATM, which in SGII land is:

TXD 07DF0178
RXF 054106780000
RXD 3810
MTH 0001000AFFD8

Believe sensor 3 downstream of DPF is:

TXD 07DF0178
RXF 032100000000
RXD 2010
MTH 0001000AFFD8

But haven't set up Xcode to have a look at that, or any other DPF related codes yet.

[watsea Member Find all posts View Profile Close watsea]

Thanks Joe for posting where the sensors are "supposed" to be located. It helps me understand some of my observations of the EGTs that I saw today.
I towed our van just over 300 km from the Yorke Peninsula to Victor Harbor in SA. Pretty flat highways with slight hills in the Yorke Peninsula then some bigger hills out of Adelaide and further south to Victor Harbor. I was observing using my TorquePro app.

The TorquePro Sensor 4 probably does not exist. A continuous reading of negative 40 C (-40 C) was displayed.

Early in the journey, EGTs for Sensors 2 and 3 where similar to Sensor 1, though their response to increase temperature under throttle was slower than for Sensor 1.
Sensor 3 initially was slower to increase its reading.

After about an hour of travel, even though the terrain has not changed much, Sensor 3 was showing a gradual increase in temperature (went up to near 600C) as was Sensor 2, mid to low 500C, and there was little decrease when coming off the throttle. Sensor 1 at low 400Cs or lower.

After stopping for fuel and coffees, then readings of the sensors became similar to each other with some fluctuations. Typically low 400Cs at highway speeds, into a slight headwind.

Of course EGTs did get hotter, 500Cs for short periods while in big hills south of Adelaide.

After reading where the Sensors 2 and 3 are, I am thinking that the high EGT readings for Sensor 3 were caused by having a burn happening in the DPF. Also similarly affecting Sensor 2. I don't have a code or display on my vehicle to show when a DPF burn is occurring. Can anyone help with that?

Joe, if the information of the locations of the sensors is correct, every Toyota is likely to be similar. So when someone mentions some high EGTs in a Toyota that cause problems, wouldn't it be likely it that they mean for EGT measured at a position as per Sensor 1 because that is the easily accessible information.

[GeeWhizz Senior Member Find all posts View Profile Close GeeWhizz]

This is what a DPF burn looks like on my Jan-2017 GX (Ie 2016 model). Bank 1 Sensor 2.

[Prado_Joe Lurker Find all posts View Profile Close Prado_Joe]

Thanks watsea

After reading where the Sensors 2 and 3 are, I am thinking that the high EGT readings for Sensor 3 were caused by having a burn happening in the DPF. Also similarly affecting Sensor 2. I don't have a code or display on my vehicle to show when a DPF burn is occurring. Can anyone help with that?

There are some good threads on OBDII codes & for DPF observation on both Pradopoint & Fortuner forums.
eg,

https://www.pradopoint.com.au/forum/...with-obd-tools

Joe, if the information of the locations of the sensors is correct, every Toyota is likely to be similar. So when someone mentions some high EGTs in a Toyota that cause problems, wouldn't it be likely it that they mean for EGT measured at a position as per Sensor 1 because that is the easily accessible information

Yes, when someone mentions some high EGTs on a 1GD it's highly likely it's based on Bank 1, Sensor 1 data - post turbo. My point is that this is in fact the EGT of interest minus the drop across the turbo. These guys

https://official.bankspower.com/tech...-is-important/

reckon that temp drop is between ~ 100 - 150C, in which case you don't really know what EGT you've got. Hence my attempt to start an EGT thread, (vs a DPF thread)

So I guess my original question should have been something like, is it feasible to bore a hole for a pyro thermocouple pre-turbo on a 1GD ?

[GeeWhizz Senior Member Find all posts View Profile Close GeeWhizz]

Some more data extracted from my CAN-Bus Monitor. The trip was from Dunsborough WA to home in the Perth suburbs (256km), towing a 2 tonne camper trailer.

Where possible, I kept the cruise control on 90km/h. The dips in B1S1 temperature (blue) were caused by having to slow for traffic. At about the halfway point we stopped (and queued) for fuel and coffee. Readings were taken roughly every 10 seconds for the entire trip.

[Prado_Joe Lurker Find all posts View Profile Close Prado_Joe]

Thanks for sharing your data GeeWhizz. I would be pretty happy with those post turbo EGTs !

I'm guessing you didn't have any significant long hills to haul up & you're torque converter is locked up in 4th ?

[GeeWhizz Senior Member Find all posts View Profile Close GeeWhizz]

I'm guessing you didn't have any significant long hills to haul up & you're torque converter is locked up in 4th ?

Spot on: the run from Dunsborough to Perth is pretty flat, along the coastal plain. The torque converter was locked for most of the time from 11:00am to 12:00pm. Data from the (inland) trip south was overwritten by the time I got home and had time to extract the data. The memory can only store about 8 hours of driving before it loops back and overwrites. My wife may not have liked me taking time out during our holiday to extract data from the CAN monitor!! We'll probably go inland on our next trip: plenty of hills to climb. (It's WA, though: you might not call them hills!)

Below is the "Motion" Data recorded from the same trip, to give some context to the DPF data, above. You can see where I forgot to pull the gearbox back to S4 as we set out on each leg of the trip! ATF and Torque Converter temperatures (separate chart) reflect this. You can see that the road is pretty flat by the steady RPM - thank god for Cruise Control!. Dips in speed, RPM and selected gear reflect traffic congestion or intersections.

[watsea Member Find all posts View Profile Close watsea]

Thanks Prado_Joe for a bit direction to those links for the DPF status. Found some information and put the equation into my Torque Pro.
So far registering as I would expect. DPF Burn happens when DPF is 100% and during that time the appropriate EGT sensors are registering high temperatures.