curious temperature guage

[marlin]

I have owned my 1997 3.0 ssrx for a week now and have noticed the last few days that the temperature guage wanders up and down ..is this normal ?
I have read a lot of threads on this site suggesting all sorts ..my truck does not appear to have any of the naughty head symptoms .. however after hearing other peoples scary tales perhaps i,ve planted a thinking seed in my head ....can anyone shead a little light on this for me where is the temp sensor so i can check for a bad connection or a wobbly wire . Also it takes around 4 miles of steady driving (not stop start stuff )for the needle to rise to the norm position ..is this normal .I probably did.nt notice the guage before as i was grinning too mutch ..however now it may be waining to a grimmace or am i worrying too mutch ?
your advices please folks

[internetsurfer]

could be the thermostat has packed up mate ( stuck open ) , temps dropping off at speed and then rising at stand still . This is my 3rd toyota and your symptoms suggest what i think

[marlin]

thanks matey but the symptoms are the other way round temp guage dropping the slower you go

[Vagrant No2]

I would go for the usual items that are covered on purchase of any Surf/4Runner . Coolant flush , stat change and new rad cap . Also operation of viscous fan .

[TonyN]

I assume your coolant level is OK?

[marlin]

yup coolant level is ok checked it testerday all fine ..no alien things in it .. baffled by the wonky temperature readings.. where is the temp sensor maybe the wires wobbly or terminal dirty

[TonyN]

Could be the sender/wiring/guage, also check the fan belts are OK and the pump isn't tight or slipping.

Can't remember where the sender is off the top of my head, been working on to many 2.4's this week!!!

[phoebelala]

I have owned my 1997 3.0 ssrx for a week now and have noticed the last few days that the temperature guage wanders up and down ..is this normal ?
I have read a lot of threads on this site suggesting all sorts ..my truck does not appear to have any of the naughty head symptoms .. however after hearing other peoples scary tales perhaps i,ve planted a thinking seed in my head ....can anyone shead a little light on this for me where is the temp sensor so i can check for a bad connection or a wobbly wire . Also it takes around 4 miles of steady driving (not stop start stuff )for the needle to rise to the norm position ..is this normal .I probably did.nt notice the guage before as i was grinning too mutch ..however now it may be waining to a grimmace or am i worrying too mutch ?
your advices please folks

Mine stays right on the botton of the normal bit and never moves no matter how heavey the foot. It takes less than a couple of miles and is always the same.

Check and replace coolant and thermostat also flush rad.

[kitesurf_phil]

Have you checked with the rad cap off (not just the header tank) because I had this when I had an airlock in the system. Open both heaters and start the engine from cold. Top up as necessary.

[NFC]

thanks matey but the symptoms are the other way round temp guage dropping the slower you go

My gauge spent last Saturday rising at speed, but not falling below the thermostat temp at all, so I figured the stat was okay (may change to be on the safe side).

Turned out that my rad was a solid block of mud. Check yours is clear as when the engine generates more heat than the clear part of the rad can shift, the temp goes up.

If you need to blast it, take the fan cowl off the back and jetwash from front AND back as a lot of the rad isn't actually visible from the front due to intercooler/aircon rad/trans cooler.

Mine was fine at idle though, so the fan's okay.

[marlin]

thanks for the input lads ive just been out on a longish test run and have noticed that the temperature climbs up to normal when going up hills and then at around50 on the flat drops down a way then free wheeling and off the gas downhills the temperature goes way down climbing again when you accelerate ..hope this helps as everything checks out ok

[chuggabug]

Hi mate, had any luck with your surf yet? Just read your article - had a similar effect on my 2.4 with temp guage fluctuating up and down, which turned out to be air in system, as I had a pourous top hose. The expansion bottle was showing a steady level, which got me suspicious, so checking the pipes I found the pipe to the exp. bottle blocked so that it could never suck back. Once I cleared this and bled system guage was fine, but it took some time to get the air out. Quite worrying seeing all those bubbles coming up!! Hope this is of some use.

[marlin]

got a new thermostat to spanner in this weekend so i,ll cross fingers and hope its that

[Tallyman]

I've got a secondary temp guage fitted to mine. Been out with the caravan over the Bank Holiday. On the way down the secondary guage was moving up and down quite regularly, even getting up to 115C when towing up a long hill on the A38 in Devon, then dropping down to below 80C on overrun downhill.

In all that time the standard guage never moved off it's position just left of centre, which it gets to whilst the secondary guage is still showing the temp as climbing up from about 50C when first being warmed up. Might be your 3rd gen has a much more accurate temp guage that's actually showing what the temp is doing, rather than the standard guage which only seems to move into the red zone when the engine is really well into the overheating area.