Please, I need help troubleshooting Pyrometer (quick video link included) (1 Viewer)

[lostworldexpedition]

I am currently driving from the U.S. to Argentina in our FJ60 with a transplant 12HT. In Colombia at the moment. The pyrometer just recently started -on occasion- going nuts, the needle just flails madly. Sometimes as soon as I start the cruiser and sometimes it takes a while... hell sometimes it does not happen at all. I have checked the connections and the temp probe (which is post turbo) and everything seems fine.

Another detail is that while driving and the pyro needle going berserk, if I step on the brakes it kills the needle. Check the video I uploaded to Vimeo to see what you think, any feedback would be greatly appreciated. I am in Colombia and heading to Ecuador, Colombia would be the easiest country to get a replacement sent if the consensus winds up being "faulty" pyro gauge (Autometer).

Link to Vimeo clip of our "problem"

My main concern is that we are heading for a lot of high altitude driving in the Andes and I would like to be able to keep an eye on the EGT, specially because I bumped the BOOST to 10.

 

[gerg]

Double check your wires from the sender. Thee are only 2, maybe the wires are not conducting well. You could also check the guage. Mine only has a wire for the light though, but maybe yours is different. I would suspect a wiring probem rather than probe problem.
g

 

[Turbo45]

do you have a multimeter with you
a pyro probe makes milivolts (I think)
so you should be able to unhook the gauge and hook the multimeter on and see if it fluctuates like your gauge does .......
if it does its the thermocouple
if its doesnt then its downstream from there
someone feel free to set me straight if im sending him down the garden path

 

[In2cruisers]

Check your ground !!!

 

[Dougal]

Check any plugs or joins in the cable. Like the one from the probe wires to the harness wires. Get someone to wiggle it while you watch.

 

[Radd Cruisers]

I've had the same thing happen with an AutoMeter... there's probably a poor connection in there somewhere that is making things load / voltage sensitive.

~John

 

[ForealBoreal]

I have heard nothing but bad things about Autometer.
I had a friend who replaced his transmission because of bad gauge wiring on his ford.
Yeah not very bright before dropping 1500 bucks before cross checking EVERYTHING.

 

[Radd Cruisers]

I have heard nothing but bad things about Autometer.
I had a friend who replaced his transmission because of bad gauge wiring on his ford.
Yeah not very bright before dropping 1500 bucks before cross checking EVERYTHING.

Autometer are generally very good gauges. Any problems we have had with them have been installation problems.

A friend replacing a transmission based on what a gauge said, is not too bright on your friend's part. Can't really blame the gauge for that one.

~John

 

[ForealBoreal]

Autometer are generally very good gauges. Any problems we have had with them have been installation problems.

A friend replacing a transmission based on what a gauge said, is not too bright on your friend's part. Can't really blame the gauge for that one.

~John

Yeah there was a lot of people laughing at him....

 

[eleblanc]

Check if you still have the ground wire from engine to frame. And also my pyrometer went nuts because vibration ended up cutting a wire just before it enters the thermocouple.

So first; take a wire and hook i up from engine to negative of battery. If that does solve the problem it is because ou have lost engine ground. If not, then your thermocouple is defective. I also use a Autometer and like i said above mine did the same and it was because the wires under the shielded section had broken. The thermocouple supplied by automter are crap and the wires too small.

EDIT: the autometer gauge are at best OK, the thermocouple is crap. And do not drive too long like that you will end up with a needle loose at the bottom of the gauge. If the pyro is the problem, get 2x from autometer and keep a spare, also tie the wire comnig out of the pyro some other way to prevent vibration.

 

[Turbo45]

ive had the same problems as above with my Autometer pyro
both times it was the wiring close to the thermocouple
when it changes with your brake lights is the only thing that makes me think its not the thermocouple
even with the wires tied up it still only last a couple years it seems

 

[lostworldexpedition]

The wiring seems sound, I think I may try to get a spare pyro sent to Colombia because once we hit Ecuador it will be almost impossible to get one until we get to Chile sometime later this year....

I have not played with the voltmeter as it has been raining, but I will give it a shot and report. I think the needle of the meter is already been a little abused by the insanely rapid movement so even if I figured out what was wrong with this unit I might need a new one...

Many thanks for the input... We really appreciate it.

 

[eleblanc]

Like i said it is 1- the engine ground 2-the wires in the thermocouple. I bet you 10$

 

[Turbo45]

unplug it before it wreaks the gauge if you need to keep driving it untill you can troubleshoot it and fix it

 

[jzilla]

I have a feeling it is the gauge itself...
Same thing happened to me several years ago. I had not had it in for a year so the parts guy gave me a new one, has been fine ever since. On that note I am redoing my turbo set-up and I am going to install an isspro.
Good Luck!

 

[eleblanc]

I have a feeling it is the gauge itself...
Same thing happened to me several years ago. I had not had it in for a year so the parts guy gave me a new one, has been fine ever since. On that note I am redoing my turbo set-up and I am going to install an isspro.
Good Luck!

I had the exact same behavior 3 times. first when i installed the gauge on my truck, my engine ground was loose. See video in this thread

https://forum.ih8mud.com/diesel-tech-24-volts-systems/153644-pyrometer-issue.html

and then on 2 occasions, with faulty thermocouple. I've since attached more properly the wire on the firewall. My guess is that i only made time until the problem occur again, shorter or longer.

Never the gauge was faulty, not saying it is not the case here, but when the needle goes like this, it is a bad contact, and since it is the engine that vibrates and not the gauge, i highly suspect wires on the engine block.

 

[lostworldexpedition]

Well, it is definitely a Pyrometer malfunction. There is nothing I can do at the moment, no $ for buying or having it shipped to South America... so I am just going to have to be light with my right foot.

I have been driving a lot of mountain ranges here in the Andes between 8 and 11 thousand feet. Much black smoke (to be expected), but the 12HT is behaving like a champ. I am trying to be mellow on long uphill drives for fear of driving up the EGT's.

Any recommendations from tried and tested diesel folks out there? Should I drop the boost down to stock 7 or keep it at 10?

Thanks.

 

[Tapage]

keep it at 10 .. boost isn't the problem with EGT's actually it helps .. the problem it's the amount of fuel that are you putting at all ..

But been driving your 12H-T so far you should know more less when it's to much right foot .. by previous experiences I mean .. so you will know how much right foot uses to need you push your EGT's beyond safe range ..