saltymoob

Hello, I wanted to start off by saying that this forum his been invaluable to me since I bought my truck 3 years ago, thank you all.


So my truck is a 1986 2wd Hilux with a 22re. About 6 months ago the coolant temp gauge quit on me and I thought nothing of it. I was living in the city centre and the longest trips I was making was about 10kms topping out at maybe 60km/hr. starting my new job in September I now drive on the highway a lot and found the truck will not shift into high gear and the temp gauge is still sitting at zero. I thought maybe this was because it's been around -10 here lately but I changed the thermostat on a whim (cheap auto parts store one) and the gauge started working and it was shifting into high again. That lasted about a week now I'm back to no temp and no high gear, did I just get a bad thermostat or is there a bigger underlying problem? Thanks for your help

Note: I have read the sticky about the temp gauge fix but I don't think that applies to me as when it is working it works perfectly and when I replace the thermostat it starts to work again and is tied to the shift issue

millball

The temp sending unit that controls the gauge is not the same temp sender that enables closed loop operation and permits the tranny to go into OD.

You may truly have problems that are causing the engine to run too cold.

Has your fuel mileage suffered??

saltymoob

Thank you for your response. I did discover the two sensors thing during my research but if both the tranny was shifting and the gauge was working when the thermostat was replaced that, to me, says that both sensors are in working order. Also my mileage is horrible, the speed on the highway is 110km/hr and I am turning 3300RPM for almost 15 minutes.

millball

Yes., it seems likely that both sensors may be good.

The engine may well be running too cold.

Try another thermostat, maybe a genuine Toyota part.

scope103

Changing the thermostat is not difficult (and not expensive), so go ahead. But you might let the truck idle for 10 minutes and put your hand on the upper radiator hose. If should be pretty warm; if only cool, I would suspect the thermostat.

saltymoob

Perfect, Ill try to source a Toyota thermostat that won't cost an arm and a leg to ship to Canada, just another thought, does the orientation of the jiggle pin have anything to do with the oporation? I have it facing towards the back of the engine.

RAD4Runner

Happy Thanksgiving!
O.P.,
If your budget is OK, and you'd like the two-stage thermostat for smoother temp control, I just got this from LC Engineering. Post shows and lists the manufacturer's part number, so you may be able to find it FOR LESS MONEY elsewhere.

saltymoob

Thanks everyone for the responses, I have ordered an OEM thermostat through a local dealer for only $37 CAD, the way the exchange rate is and with shipping a 2 stage would come out to $100+, but I may come to regret not buying one straight away, but i'm willing to take that risk, head gaskets are cheap right?

saltymoob

So I bought an OEM Thermostat from a dealership ($48 CAD) and everything seemed to be running well except that now for reasons I cannot comprehend the temperature will sometimes creep up and up and then drop, sometimes it gets all the way up to just under the red (At which point I pulled over and shut it down). I thought it might be a fault with the gauge, but when the temp gets up there I can smell the engine. I have added coolant and burped the system several times, totally at a loss at what to do. But the new thermostat has solved my shift issue and the gauge seems to be working fine

RAD4Runner

Do not assume anything. Actually check. See how I knew, on my THOROUGHLY cleaning temp sensors post.