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Just can't seem to get a break...


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:banghead: Darn it all... I'm wondering if this issue is coinciding with my previous post on the paculiar rattling noise I was having. It seems my pyro gauge is no longer functioning... I dunno if it is the gauge itself or if it is the probe. My money is on it being the probe. I noticed when I got home from the grocery store that the pyro was at 150 degrees. No way I can ever drive light enough to get it that low. Engine idle does not even allow it to be that cool. So, I opened the hood, no apparent signs right off the bat. I had the driver door open and hood up. Cranked the engine, made a funny noise. Let it run for a second, to see if the inoperable gauge is just a fluke. Nothing. Shut it down and made a funny noise and louder sounding than when started. Can't quit place my finger on what it could be. Never heard such a noise. I have good oil pressure and my oil level is at the half-mark between full and fill. So it should not be bearings. Does not have a knocking type of sound... I have a theory. Tomorrow, I will have to inspect the turbo. I'm wondering if the pieces of the probe broke off and is in the exhaust pipe rattling around. Hoping that the debris did not cause a turbo failure? Is any of this plausible? What can I do to diagnose the pyro, and if it is the probe, where to get one? I could not space this whole thing into paragraphs either, sorry.

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I am going thru the same thing, but narrowed mine down to the gauge itself. Anyhow ISSPRO sells type K thermocouples, pull yours and see how it looks. Is yours a true mechanical pyro, or does it have a elec stepper motor?

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The first thing I would do is pull the probe. IF there is a piece of the thermocouple in the turbo you risk major damage and expense.

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I'm not sure about what kind of gauge mine is. I know its a dipricol egt gauge. I can't find any info on dipricol and what kind of probe to use.

I have been reading a little and some say check a ground to something. I dunno if this sort of thing applies to me though...

I sure 'am worried about this noise that it makes on startup and shutdown and when it is idling in drive... ugh. :banghead:

I sure can't afford an expensive repair right now!

--- Update to the previous post...

Okay, got some pics of my problemo. I checked the oil level just in case. Was good. The EGT gauge was not at zero, depsite sitting overnight.

Removed the probe to inspect it to see if it broke. Although, it looks exposed. I suspect it happened when I pulled it out. When it went back in, some of it flaked off more.

I tried to get video of the noise, but with my cell phone, it has crappy sound quality. So it was not even worth posting.

I'm also wondering, could an injector leaking internally make the sort of noise? I could definitely hear the noise in the exhaust line. Has like a tinny noise. Or maybe valves need adjusted? I'm at a loss...

I also inspected the turbo, un-offically. The shaft spun freely and did not feel like it had any play. I know it spooled up fine when previosuly driving it despite this noise.

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That little flake is nothing but some soot. Nothing to worry about. If you can separate the wires going to the probe do so and check the voltage generated (yes, that is how they work) with a DVM set on milivolts. I don't know how much it makes, but it should vary as to how much the temperature of the probe rises. The warmer the probe the higher the voltage. Far as the gauge not reading zero, unless yours did before then it is normal. Mine has never been below 175* in over ten years.Now as far as your noise, what part does it seem to be coming from? Head, exhaust, lower on the block? Check to make sure you don't have any tin rattling on the exhaust or in the muffler. Something to try is to use a dowel to listen to your engine. Put the end of the dowel where you want to listen the use one hand to grasp the end of the dowel so that it is not sticking out of your hand. Put your ear up against your hand holding the dowel and you will be able to pin point a lot of different sounds.

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I would try a new probe myself if its not like the gauge AH64ID got with the stepper motor and signal amp. I've got a old school DiPricol gauge with just the probe. So if there is no box then I would try a new probe.

MIKE! How ya been my man!

I believe I just confirmed your assumptions:

I tracked down some info on testing the gauge and probe. I took the probe out and hooked up a DMM and tested on the Ohms side. It was reading less than 1 ohm at ambient temp. Took a torch and heated up the probe. Got a reading on it and watched the ohms fall as it cooled. Disconnected the probe leads and took a 9v battery and tested the gauge. Gauged pinned out at 1600 degrees.

At this point, I was really confused. Took the probe and tested it separately. Torched the probe, no change in Ohms. 0 across the DMM. Probe is faulty.

Surprises me though. Wonder why it would change in ohm value when it was connected to the gauge but did not change when separately.

So, I'm extremely happy it was not my dipricol gauge. Looks like from more reading Dipricol is no longer in business. I did not want an odd gauge with my setup, lol.

Ok, so what type of probe, and where?

BTW, my EGT dipricol gauge is just a 2-wire lead for the probe. Does not have a box or anything extra, etc.

--- Update to the previous post...

That little flake is nothing but some soot. Nothing to worry about. If you can separate the wires going to the probe do so and check the voltage generated (yes, that is how they work) with a DVM set on milivolts. I don't know how much it makes, but it should vary as to how much the temperature of the probe rises. The warmer the probe the higher the voltage. Far as the gauge not reading zero, unless yours did before then it is normal. Mine has never been below 175* in over ten years.

Now as far as your noise, what part does it seem to be coming from? Head, exhaust, lower on the block? Check to make sure you don't have any tin rattling on the exhaust or in the muffler. Something to try is to use a dowel to listen to your engine. Put the end of the dowel where you want to listen the use one hand to grasp the end of the dowel so that it is not sticking out of your hand. Put your ear up against your hand holding the dowel and you will be able to pin point a lot of different sounds.

Thanks for the info, man! So was I wrong in using ohms, or will it still work? I'm not sure if I my DMM measures milivolts. Its an auto ranging DMM. It has A/C and D/C selection though.

I will TRY and see if I can get a video of the sound the truck is making. Its not a constant noise and only happens intermittently. I could definitely hear it coming from under the truck. Well, atleast I think so, cause the engine and exhaust make so much noise. It does not sound like it is coming from the engine per se.

BTW, if my EGT gauge is "indexed" at the temp it sits cold, does that mean its really cooler than what it reads?

--- Update to the previous post...

okay.... so the rabbit hole is a little deeper... :banghead:

http://forum.aempower.com/forum/index.php?topic=22888.0;wap2

I decided while I had a moment, I would test the probe with my DMM on the volt setting. The auto range was already on mV's. With the link above, using the values listed. I torched probe. At red hot, the probe was putting a mV value at about 1k to 1.2k mv range.

Values slowly descended as the probe cooled.

WTF! :shrug:

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You have the pre-stepper motor gauge, I agree with trying a new probe. Get a type K thermocouple with the two nut connections like you have now. Any type K should work, but I would call ISSPRO for ease of getting the correct part number.

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Your auto ranging DMM should give you milivolts. I suggest using the values that were from your link:400F - 8.32 Millivolts800F - 17.53 Millivolts1200F - 26.98 Millivolts1600F - 36.17 MillivoltsLike John said, just use a type K thermocouple. Just don't call it a thermocoupler like some do (one of my pet peeves). It don't couple anything.......

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:doh: I swear, I have never had a vehicle that was so finnicky... ANOTHER, fluke! :ahhh: I broke down, was ready to order one online. I had to put the probe back in the hole to plug it, and I hooked it up one more time to see if the gauge would read. Just for Shiz's and giggles. Took the torch to the probe, looked at the EGT gauge, and it was around 700 degrees. :duh: ...what is this? Well, I guess I don't need to order one, yet! I also narrowed down the location of the noise...
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Depending on the torch that may be a bit cold, or you had a loose connection. Give it a try and see what happens, maybe it had too much soot on it. When was the last time you gave her hell and saw some good EGT's?And the noise was????

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Depending on the torch that may be a bit cold, or you had a loose connection. Give it a try and see what happens, maybe it had too much soot on it. When was the last time you gave her hell and saw some good EGT's? And the noise was????

I believe I'm using regular propane. Its a yellow bottle, but I'm pretty sure its propane and not MAPP gas. I was thinking I may of had a loose connection, too. I'll run it around for a little and see if I'm getting worse. If so, I'll order a new probe. I actually have not given her, "hell" much at all. Lately, I did some around town driving. Did not get warmed up even. Have not driven it much since then. If I WOT it, EGT's can get to 950 degrees on the flats. I can get to 1050 on the hills around here. But it is for a short duration... I need to get my trailer going for firewood, so hopefully I can tow that around soon. EDIT: The noise will be discussed in my thread.
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Those EGT's seem low for what appears to be stock tuning with injectors. Should be able to hit 1200° or 1250°.

:ahhh: When I cruise down the freeway at 60mph it is usually at 700 degrees with the injectors I have now. It would have taken me to go 70mph to hit that EGT.

Well, I better order a new one then, just in case for peace of mind. Wish I had a potentiometer so I could apply a specific amount of mV and test the EGT gauge.

I hope this is not the cause for my funny noise. As in I cooked my turbo or something from faulty EGT readings...

--- Update to the previous post...

Oh boy! So I just ordered one. Hope I did not pay alot for it.

Only place I could find one:

http://www.dieselpowerproducts.com/p-5910-isspro-k-type-thermocouple.aspx

Hmm... I wonder if an article should be composed for diagnosing EGT problems.

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Okay, got my EGT probe in today. Its an Isspro. I'm not sure what the one was that I got when I bought the truck, but they are different. Fittings were different than the one on the truck. Luckily, the probe was the same diameter. Came with a ferrule, so I stuck that in with the old fittings and tightened it down. Seems to hold. Thought it was not gonna work initially!Upon driving, I noticed that the gauge reads different values than the old one. As in, upon decent acceleration, I can make the EGT's go up to 800 degrees. Then cruising at 30mph or so, it hovers at 400. When I park and idle for a minute or so, the EGT's fall quick and show a lower temp. reading than compared to my old one. Rarely did I see my EGT's go below 350 on the old one. Now, it will go to 300 and lower fairly quickly.So all in all, sure, it was a good thing to replace. Shows a more accurate temp reading, but does not seem to vary much compared to the old one when driving. Time will only tell, I suppose.

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Without having a calibrated gage, to check yours against your just trending anyway. This is truly one of those time will tell situations. The setup as you have it will show you enough information to make an educated assumption based on observations of the gage over time. :whistle: I'm just points hunting with this post anyway:thumbup2:

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