Ext.temp Hitting 1000 Degrees And Over :(

[13Beast]

Hi there,

I know its not a skyline, but, I've been a member on this forum since when I owned my '32 GTR, and I value what knowledge there is on this forum - so maybe you guys can help me out on this one

I was driving my MR-2 today and noticed the Ext.Temp gauge rocket up to in excess of 1000 degrees celsius - well into the red zone on the gauge.

Knowing that high ext temps can often mean serious detonation, I drove it carefully out of boost the whole way home (I'd been driving it like a nanna all day - 50km/h road limits here in Japan!).

I switched it off to eat dinner. Came back out after 90 minutes, and it rocketed back up to 1100 degrees within minutes of starting it up again.

Couple things confuse me though - the reading went from the low part of the gauge to the upper part of the gauge within minutes of driving. Nothing gradual from the looks of things, although I wasn't staring at the gauge the whole time. I looked back after 2-3 mins and it was back in the red (after starting the car at the low end of the gauge).

I wasn't driving it hard at all (all below 4k rpm, well out of boost), and the car was behaving normally as it always does. No other signs of untoward worry - fuel pressure was fine, as was oil/water temp, no smoke, no pinging, nothing.

The car is running a Trust TD-06, aftermarket cams, AVCD and an Apexi Power FC among many other things.

Any ideas? Have I got a faulty gauge? Or is there something possibly terminal lurking under the hood that I should be worried about?

[Cjmartz2k]

If you are indeed seeing temps of 1000c+ for more than a second or two, a lot of things should be glowing orange/red under the hood like the exhaust housing of the turbo for one. Is the temp fluctuating with throttle input? What is the temp at idle?

[13Beast]

The gauge is a GReddy gauge and reads on a scale of 4 - 12. Each being x 100 degrees celsius.

It was sitting at between 11 and 12 on the gauge. Not fluctuating at all with idle or throttle input. Dead steady as a matter of fact.

Oil and water temp also completely unchanged.

[Cjmartz2k]

gage problem

[GTR-32U]

I reckon you got a guage problem for sure, or the pickup is faulty.Have you had a look under the hood when the guage is reading so high ? Anything look glowing orange ? Is the heat coming out seem excessive compared to previously?

[Duncan]

cat partly blocked or similar? if its true its damn high

[QUICKY]

+1 Duncan

if the gauge is working fine, then ide guess u got a blocked cat

[tridentt150v]

gauge or short in gauge wiring, check your wiring before ditching the gauge. Alos check your sensor, if you can borrow another one and use it give that a go.

[paulr33]

leave the car off over night

what does it show next day

[13Beast]

Car has no cat. I'd say if it was a blocked cat, there'd be power issues as well due to the restriction in the exhaust.

The wiring is unbroken, but does look a little old.

Drove it today, and the gauge again was showing a high temp, but would often drop back down. Considering there seemed to be no correlation between idle, throttle on/off and the reading on the gauge, I'm %90 sure its a faulty signal.

When it wasn't peaking off the dial, it read around the 550 degrees celsius mark which is close to the bottom of the gauge. No A/F meter handy so I can't say for sure though... Will definitely get it sussed out properly - not worth taking a risk and ending up with a dead motor