Is EGT probe stuffed?

[Deevo]

This weekend I fitted boost and EGT gauges to the Troll. The 2 wires from the probe are wrapped in a woven stainless steel sheath and come coiled up in the box. Whilst feeding the the probe wires through the plumbing adjacent the clutch M/C, the coiled sheath unravelled and touched the positive battery terminal. The SS sheath had 2 scorch marks but I soldiered on. When I went for a 5 minute test drive, nothing happened on the gauge. I disconnected the 2 probe wires and found there was continuity between them so I assumed the inner 2 wires had fused together at the 2 scorch points. I snipped the sheath back and found the wires were discoloured but not melted. I then separated the pairs of wires and checked for continuity again - which it had. So .... should there be continuity between these 2 wires when the probe is cold or should it be open circuit? i've checked the other wiring against the instructions and that all seems OK. The gauge even lights up when the parkers are switched on. Any advice anyone?

[GeeYou8]

There should be only a few ohms on the probe, it is just 2 different types of wire welded together at the tip, the different metals produce a very small voltage proportional to the temperature difference between the probe & the gauge.
is it a digital or analogue gauge?
If it is analogue try reversing the probe wires.
Graham

[the evil twin]

What GU8 said ^^^^

Thermocouples are suprisingly robust and having continuity is a good sign.
Check from each wire to shield, that should be very high.
If that all checks out and it still doesn't read the EGT, swap the wires around.

[Deevo]

Graham.
The gauge is analogue and the wires can't be reversed as they're male and converse female bullet connectors. I've been back to Autobarm and they're prepared to let me swap components to see if they're faulty. The guy said they have very little trouble with Saas gauges ..... I bet they say that to all the boys;)

[Deevo]

Thanks Evil Twin. Please see reply to Graham. When you say 'Check from each wire to shield, that should be very high' do you mean high resistance or high continuity?

[GeeYou8]

Deevo
High resistance, should be open circuit.
BTW Devo was my nickname when I worked in Melbourne for Ansett.
Graham

[Deevo]

Thanks Graham. Ansett hey. That must have been a long time ago! I suppose not too many on this forum would know what Ansett was. We're both giving our age away :)
And as for my nickname of Deevo, well that's a very old stone best left unturned.

[Deevo]

Well here's the latest guys. I took the car down to Autobarn and we installed a new probe. No change! Next we fitted a new gauge. No change again. Then the sales guy had no option but to get under the dash and check out my connections. He agreed I'd wired all the right colours to the right sources. He had no more ideas, so gave up. The only thing we didn't replace was the short cable that runs down the A pillar from the gauge to near the accelerator pedal. I decided to wriggle the wires while the engine was running and suddenly the gauge read. I thought it was a dodgy crimping into the bullet connector so I soldered it. This didn't fix anything but if I touched the bare connector with my finger the gauge read. If I touched it with anything metal or left it alone, it read nothing. What the hell is going on? I then did away with the M + F bullet connectors and soldered the wires directly to each other. Nothing! But the moment I touch it with my finger it reads. Any ideas would be great and a solution would be even better.

[LostBenji]

Graham.
The gauge is analogue and the wires can't be reversed as they're male and converse female bullet connectors. I've been back to Autobarm and they're prepared to let me swap components to see if they're faulty. The guy said they have very little trouble with Saas gauges ..... I bet they say that to all the boys;)

OK, I can answer this. I too have had issues with EGT gauges. The first unit I used (Chinese - eBay Job) was shocker for under-reading (nearly 100° under actual). The second & third were the SAAS gauges, OMG, whats pieces of shit.
Mine were bought from loca Autobahn who also told me the same line, no issues with them. First unit would randomly go all over the place and scared the shit out of me when it went up to 900° while on the highway. Gauge was swapped out after excuse like above was given. New one worked for a week then fark me, again, rock-show.

After a well place thump (yeah, I smacked it), no issues again till the other day when I washed the car (and under the bonnet), the thermocouple and lead got wet.... Took a solid day to dry out and work again. The SAAS stuff is cheap-n-nasty. The next gauges i use will be likely something like Autometer.

[Deevo]

OK, I can answer this. I too have had issues with EGT gauges. The first unit I used (Chinese - eBay Job) was shocker for under-reading (nearly 100° under actual). The second & third were the SAAS gauges, OMG, whats pieces of shit.
Mine were bought from loca Autobahn who also told me the same line, no issues with them. First unit would randomly go all over the place and scared the shit out of me when it went up to 900° while on the highway. Gauge was swapped out after excuse like above was given. New one worked for a week then fark me, again, rock-show.

After a well place thump (yeah, I smacked it), no issues again till the other day when I washed the car (and under the bonnet), the thermocouple and lead got wet.... Took a solid day to dry out and work again. The SAAS stuff is cheap-n-nasty. The next gauges i use will be likely something like Autometer.

Thanks for the reply Benji.
Since the last posting I've taken the car to an autoelec and had the wiring checked out. He spent nearly an hour on it and said the wiring was all OK and he could find no reason why the gauge shouldn't work. I went back to Autobarn, showed the autoelec's invoice and asked for a whole new everything. Got a third guy this time and he said the same as the previous two guys - no SAAS gauges have come back for warranty yet plenty of Autometer have. Anyway, he replaced it. Got home and carefully fitted it all up and because I didn't trust the thing, I only twitched the wires together. Bloody thing didn't work! Then when I touched the wires to untwist them it suddenly worked (the engine was already hot). So I thought, nothing to lose, I'll crimp everything together. So I did and it worked and it's still working. I don't know if they're crap or not but it's put me off them.

[LostBenji]

Bloody frustrating as hell, ins't it?

[johno90]

Ive tried then all and only trust autometer in both my patrol and chevy always accurate and never faulted. Its expansive but much cheaper in the long run.

Sent from my SM-G935F using Tapatalk

[mudski]

Strange issue that. If your touching the connector and you get a reading. Would that mean your earthing the connection?
As for gauges, I haven't tried Autometer myself, they must be good as you see them on the bonnets of riced up Gemini's and race cars. Lol.
I however would vote for VDO, or McNally then Redarc.

[threedogs]

Would this help ,,,
http://www.ebay.com.au/itm/251654512567?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[macca]

Strange issue that. If your touching the connector and you get a reading. Would that mean your earthing the connection?
As for gauges, I haven't tried Autometer myself, they must be good as you see them on the bonnets of riced up Gemini's and race cars. Lol.
I however would vote for VDO, or McNally then Redarc.

Was a sealer used to install the probe? Insulating it from the exhaust and "earth"


Ive tried then all and only trust autometer in both my patrol and chevy always accurate and never faulted. Its expansive but much cheaper in the long run.

Sent from my SM-G935F using Tapatalk

Have you tried SPA, the one in my car was also in the last and has been in use for 11 years without fault.

[mudski]

Was a sealer used to install the probe? Insulating it from the exhaust and "earth"


Not sure what he used macca. But it does sound like an earth or something to that affect when he's touching the connection.

[johno90]

Was a sealer used to install the probe? Insulating it from the exhaust and "earth"



Have you tried SPA, the one in my car was also in the last and has been in use for 11 years without fault.

Cant say I have, In saying that ive never needed to buy another gauge once I purchase an autometer one. They look about the same quality tho :D

[RicaIii]

Hi...i am a new user here. In my case issues were there with EGT gauges. The first unit I usedwas shocker for under-reading . The second & third were the SAAS gauges, OMG, whats pieces of shit.Mine were bought from loca Autobahn who also told me the same line, no issues with them. First unit would randomly go all over the place and scared the shit out of me when it went up to 900° while on the highway. Gauge was swapped out after excuse like above was given. New one worked for a week then fark me, again, rock-show.

[threedogs]

Deevo
High resistance, should be open circuit.
BTW Devo was my nickname when I worked in Melbourne for Ansett.
Graham

What years were you at Ansett Melb, most of my mates were either
TAA or Ansett back in the day

[threedogs]

Hi...i am a new user here. In my case issues were there with EGT gauges. The first unit I usedwas shocker for under-reading . The second & third were the SAAS gauges, OMG, whats pieces of shit.Mine were bought from loca Autobahn who also told me the same line, no issues with them. First unit would randomly go all over the place and scared the shit out of me when it went up to 900° while on the highway. Gauge was swapped out after excuse like above was given. New one worked for a week then fark me, again, rock-show.

Dont forget to post an intro, just something we all have to do,
No harm done though, I have Speco boost and no idea on boost
gauge but should of brought "C" instead of "F"