exhaust gas temp 3 fault??

Un burnt fuel will pass right through the DOC, but soak into the DPF. After the injector failure the DOC and DPF should have been removed and cleaned/inspected for any damage. If you are getting excessive temps there could be some fuel still in there and some DPF melting. Better get this checked out. If you do get the DPF cleaned, I recommend to also get the DOC cleaned too.

 

I am haveine opposite temp issues. We plugged my Paccar max into a computer and my exhaust temps are not reaching the high temps. I’m getting about 800 degree and the regeneration never finishes. This is on a 2011 truck. Don’t know what to look for first so any help would be appreciated.

 

Inspect for exhaust leaks. If none are found clean and flow test the fuel doser as they get caked over with carbon. Also make sure the backpressure valve is free at the yoke and goes to full travel.

 

Don’t bother testing a doser unit. Costs the same to replace it with a new one. If no exhaust leaks were found and a new doser didn’t fix it. Have the Doc, DPF cleaned. I got charged like $3k in the shop Over a month total in two months time and all the time it was a $285 doser

 

I got a pacar mx13 in a Pete 386 and I just got a exhaust temp to hi and no codes whats that mean

 

High exhaust temp or HEST is a normal warning to warn the operator that the exhaust temperature is above 500F and ussually at speeds below 5mph.

This is normal operation and not an indicator of a malfunction.

 

Been having some SPN 3245 codes lately also. 2008 Cummins ISL 425HP. Has DPF/EGR, no DEF. Apologies in advance for the long explanation, feel free to skim over or skip parts as you want but I thought I should include all the information in case it helps. Will start at the beginning:
Probably about 5000 to 8000 miles ago we had a coolant line blow, that made the bottom half of the engine compartment including the DPF area quite wet. After that we had a amber check engine light that would come and go every 50-100 miles or so, it was SPN 3245 FMI 2. Also showed MID 128 SID 328 FMI 2. (I am guessing these 2 codes are the same thing in 2 different formats?) FMI 2 based on my research is data erratic, intermittent, or incorrect and based on this thread SPN 3245 is the EGT #3 sensor. That code came and went for maybe another 2000 miles, and I heard somewhere that it could mean dpf plugged. We did a dpf cleaning with a pressure washer (didn't bake it like many suggest, but got a lot of soot out). Then about 1000 miles after that, we got the red stop engine light, SPN 3245 FMI 0, I've heard FMI 0 is High - Most Severe. So a high temp EGT. Turning off the key then back on reset the stop engine code/light but it would come back after a mile or so of driving. Let it sit overnight, did not have the stop engine for probably another 3000 miles, but the amber check engine SPN 3245 FMI 2 (data erratic, intermittent, incorrect) came back intermittently. Lately we have been having the stop engine SPN 3245 FMI 0 light more often, sometimes after sitting for 5 mins and turning the key back on the stop engine is still there (if it was really too hot, it probably would have cooled down enough by then to no longer register the code?) Then turn off and back on again, and when turning on the key, it was not there, but about 15 seconds later with the key on before even cranking up the engine it came back! (How could it have heated back up without even running the engine?) Lately we have just been restarting it and driving as far as we can before it shuts down, sometimes the stop engine comes back quickly and other times we can drive for many hours without it coming back, but usually have the amber check engine light come and go between stop engines - can't veryify exactly what that code is since you need to have the park brake on to read codes, but its probably the FMI 16 or the FMI 2. On 2 occasions of stop engines, upon turning the key back on we still had the stop engine (SPN 3245 FMI 0) also the check engine (SPN 3245 FMI 16, from my understanding meaning temp high - moderately severe.) AND the High Exhaust System Temperature warning (which I understand is normal and indicative of a regen). But the odd thing is that these 2 occasions were the ONLY times I ever saw the HEST light in over 25k miles of owning this vehicle.
So that's the rundown. Not sure if when I get these stop engine codes if its actually overheating or if the sensor is bad. Thought I would post and see your thoughts, @Heavyd and other knowledgeable members. I do believe it could be a bad sensor because:
1. Have not seen the HEST light other than the 2 occasions mentioned above, like it is not registering anything.
2. Have had engine lights indicating erratic info from this sensor.
3. This issue began after a coolant line blew, maybe something got wet.
4. Checked the wire connection where the EGT sensor plugs into the harness, and the connections were clean and not corroded. (Not sure where to trace the wires to see if there may be other connections that could be bad...)

Not to give too much of an overload of information, but also should maybe mention the following two things, just so I don't leave anything out. They may not be too important. First of all before we bought the vehicle there was a check engine light, and the previous owner said that he was told that replacing some wire harness was the fix, but ended up getting the code cleared without the fix, and we did not have a check engine light until after coolant line issue. I do not know what the code was before we bought it, if it was related to this issue or not.
Second thing I should mention, is about 200 miles or so before the coolant line blow and the start of the check engine lights, there was a flashing regen required light that came and went twice.... Then never came back since. Like I said, never saw a HEST light though.

What are your thoughts on this? Basically trying to figure out if the sensor is bad or if there is actually an issue causing the exhaust to overheat...

Thanks.

 

I would say you have a sensor or wiring problem for the #3 temp sensor. It would be best to get Cummins Insite connected to see what the other temp sensors are reading, especially after sitting for several hours so if all sensors are reading ambient temps but #3 is unrealistic, you know it's a sensor or wiring. The high exhaust temp light will only come on when the truck is stopped or moving slower than 5mph, so this might explain why you don't see it often.

 

Thanks for the reply. It would be useful to hook it up to insite.... just don't have those tools available at the moment and trying to figure out if it may be safe to limp it 1200 miles home with the sensor disconnected until we can look closer at it, which it probably is safe.
I have not had any codes for any of the other sensors, so it probably wouldn't be too hot right out of the engine like you said previously.
You did mention in a previous post that it may be possible for there actually to be an over temp problem with this one sensor only and not the others if there was an issue with the doc not properly burning the unburnt fuel and it getting caught in the dpf and burning uncontrollably in there..... but it sounds like based on the fact I have gotten FMI 2 codes and how this stop engine code comes and goes unpredictably, and sometimes even appears when stopped, it is highly unlikely I have an actual overtemp problem and more likely a faulty indication?

 

When a regen is happening, or some sort of uncontrolled fueling event to cause higher temps, you can usually smell it when it is happening. If you can't smell anything out of the ordinary, its probably just a sensor problem.