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Discussion Starter · #1 ·
So i have the edge monitor and it consitantly reads 200 degrees higher then my autometer gauge. The sensors are located no more then 3/4 of an inch apart. The consern is that my truck on stock settings or turned up with edge and mp-8 is running around 1250 according to the edge and 1050 on the autometer gauge. I tend to learn towards the autometer but would like to know if anybody else has ran into this and what i should trust more?
 

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First off I would have to ask where did you put the two sensors in the exhaust stream? Then if they are 3/4" apart as you say I would want to see a PIC of them myself? My concern with this setup would be one of exhaust restrictions with the two probe's drilled in and mounted in certain places that close together. There is only so much room in the collector on the exhaust manifold for the exhaust to enter the VGT, if you mounted the probes there.

The collector on the exhaust manifold is actually really thick where I tapped mine in. I was concerned enough with the probe being mounted in the stream of the exhaust in such a small area where all the exhaust is gathered and has to pass through, I mounted my probe over to the side of the collector area, so as to just be close enough to get the reading from the heat, but be just skimming the very edge of the pathway. Mine is more in the thickness of the wall of the collector.

Now I have not mounted anything but one in mine so far, but do have plans for another for a dedicated EGT guage and that way I can use other data gathered by the Juice and use the EGT guage only for it. I will put the other right straight across from the other and down stream much as possible to get less restrictions from the two probes.

Now if a person was to have two probes running straight inline with each other and one up stream and one down that are 3/4" apart as you may have, I figure that would be ok far as any restrictions, but that alone could be the difference in temps your seeing from one guage to the other...

Something you might can try if the sensors are the same as many I have seen, far as how the hook up, try swapping the two sensors to the other guage from how you have them now and see how things may read!!! Might be for some interesting experimenting...
 

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Also might try swapping the sensors in their holes to see if the temps reverse or not. If not I'd try putting them both in boiling water to see what they read. Boiling water may not hot enuf, but worth a try.
 

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Discussion Starter · #4 ·
Well im no diesel expert but my gass race engine experience I know a lot about flow and how it reacts to things. My probes are right in the middle on the top pointing down towards the turbo were edge recomends. Had to remove a lot of junk to do it so hope it was ok. I really don't think it could be a flow problem pluss looking at that stock manifold its nothing to scream about for performance like you said thick! and narrow. I hope for an aftermarket one soon. The boiling water may work the best I was looking at the numbers and i think the sweep on the autometer goes off a different range but still try it maybe last lot to go threw to get at thoughs wires again. I was also under the impression that mounting a sensor like u did can give you a hole nother set of problems you catch all the heat off the wall of the manifold get false readings thats why they say to go right in the stream?
 

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Now mounting the probes as you did is an interesting idea I must say I never thought about doing in that way. I will also say that I see what I would consider to be high EGT temps, but I just figured it was due to the EGR and how hot in general this motor runs... I don't like the idea of 212F degree coolant temps. Let alone the 1100-1270's I see quite often for EGT's...

Now I guess I could be experiencing some of the issues with off the thick walls as you say. Heck I don't know for sure, I just know what I did and what I am seeing with mine now.

It would be interesting to see what differences you would see if you could swap probes to the guages or as mentioned move the probes in the exhaust manifold and see if any differences... I fear boiling water is sure going to be way down on the range of the guages and may not be a good reference point that low of temps... I do look forward to see what you do and find out though dude LOL!!!
 

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Discussion Starter · #6 ·
Well today all i got around to was swapping the positions. It didn't change anything. But at cruising speed around 70 my readings are in the same range as yours even seen 1300 but engine temp has never gone above 200 that i have noticed exluding the fact that it is probably much cooler here then were you're running. Hey what difference did you feel with the hot unlock?
 

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Dude, the hot #6 was just a little more of the same and more temps and alot quicker temps LOL. I have seen 1500 and was still acting like it would keep right on through the nuclear part where the pistons all melt down and fall in the bottom of the oil pan LOL...

Mine might not be even close as bad as she is if I had more fuel coming to the injection pump. I know my truck has a really low suck lift pump system and one that I am going to be changing to the Raptor 150 with some other changes also. I have all intentions of putting way more fuel to the system on the cummins so as to have the extra fuel for better cooling of the componets and come back down the by-pass line to the tank.

Now one other thing I see on mine is the OEM temp guage on the dash, it seems to be almost dead on at 200 degrees, but when its just a very little bit over or under the 200 mark, there is a 10-15 degree change according to the Attitude moniture system.

I have also bought me a new 180 degree stat I want to put in and try. The stat in these 6.7's is a 195... Now I am sure the hotter stat helps with things like regen and cleaner burns on top of the pistons and all. I am also sure the hotter the motor burns the better they run too. How much so, I have no idea just yet, but I plan to see what kinds of differences it makes though.

I will be mostly curious as to how the PCM and ECM changes things to help the motor adapt to this new cooler stat. I would like to hope for a cooler running motor first off, but I don't want it if it takes another MPG of fuel to do so LOL... This motor as smart as it is, may in fact use more fuel to try to get the heat back LOL... I am also most interested in the fuel timing knock I have from time to time or all the time when I delete the EGR system, if it changes this any??? The temp change could make for some interesting things to check out, then the PCM and ECU could move things around and you may never see a darn thing different LOL... I will be for finding out.

I did some reading in the service manual on these motors and I found that the ECT sensor sends a signal to the PCM for a host of calculations and more than a few of these are of great interest of mine and trying to figure out this fuel timing knock issue I have to get my EGR off this motor... The temps of this motor has the PCM changing things all over, one being the EGR solenoid on/off times and this affects the EGT's as well... It also affects the injector pulse width where is one of my area's of great interest to see if this ain't where the fuel timing knock comes from...

These motors do seem to run way more EGT's than the other diesels I have had over the years for sure, this one being my first Cummins though has me concerned somewhat as I am not sure what the Cummins has been doing before this motor...
 

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another way is to hook both guages up to the some probe if there the same then your good if there still diff then one is reading wrong.
 
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