The temperature guage on my 85 22RE SR5, has been acting strange lately. Sometimes it works fine (not often, but some times). Most of the time, it will jump to just below the half-way point of the guage and not move. (I only notice because it starts having this reading way before the engine has had time to actually warm up.)

Is there anything I can do to try and fix this, or do I need to just buy and install an aftermarket guage?

 

There is a coolant temp sensor near where your thermostat lies. Just to the right of where your upper radiator hose attatches to the engine are two plastic plugs with electronic posts underneath them. Label them, take them off and spray them out with electronic connector cleaner. Then take some sand paper and brighten up those posts, careful not to break them. Give that a try, if your problem persists buy a new coolant temp sensor...Also make sure your thermostat is in proper working order JIC.

 

a good ground at the dash cluster is also needed for the gauge to work properly

 

My 87 22re also does the same .I tried the" tighten the brass screws on the back of the instrument cluster" worked for about an hour. The wiper on the potentiometer for the gage is dirty.If you want to keep it original you can remove the cluster and send to one of many shops that specialize in disassembling and repairing them(not cheap nor fast) I would recommend installing a aftermarket ELECTRICAL gage (no fluid in the passenger compartment)I installed an Eques gage for $27.00 (amazon) It had a new sender unit,adapter(m16x 1.25) and 1/8npt.I can now watch the thermostat open and close!Much faster than factory .All wires for hook up can be found behind the cluster as long as when you install the sender(located on top of the intake manifold below the cold start injector,one wire (yellow/green) My 2cents

 

dude, you are talking about the temp sensor that goes to the ECU, not the cluster gauge.

please do not give advice/instructions unless you are somewhat sure about what you are talking about.

 

redbayredneck,

i just got an SR5 cluster that is doing exactly what you are describing, even when i disconnect the temp sender wire (should read minimum if you do that).

my temp sensor in my DLX cluster has been working fine also, so I know that it is the cluster.

please measure the resistance on your temp gauge on the cluster to compare. mine came out bad...
(normal)

IG-E 84 ohms (273)
TU-E 162 ohms (138)
IG-TU 78 ohms (135)

 

Boy This sounds like a seat belt thread and I thought I was the only one three inches hanging out my door LOL

 

A couple of more points . once you install your new gage depending on your thermostat you will notice some interesting things.because the new gage reacts more quickly to engine temp changes. I have a chain store 180f t- stat.During the summer ( La-TX on the gulf =HOT!) it moved to 160 /170 with A/C on and stays there.However now that it has cooled off to32 F at night(BOY its cold! lol ) and I am using the heater you can watch the temp rise to 180/190F and then drop down to 160/170F. Anyone care to comment on how the cooling system flows when the heater valve is open. I really like my after market gage plus it gives me something to talk about ! You know you drive toyota when.......

 

I would measure it, but I don't have the tool to do that with. Might have to hunt down one of my buddies that has one.

 

Because covering basics is a bad idea? I suggested me made sure 2 connections were cleaned and his thermo worked fine. Its not like I told him to splice wires or create a by pass...my temp guage acted funny too I changed a thermo and cleaned those connections on my 84 and it came right back. It might have been a freak thing but it worked for me...just saying.

 

fix this problem yet bud?

 

No I haven't, I cleaned the plug for the temp gauge hoping that that might fix it last night. I am not sure that it even made a difference. My next stop will be to check the cluster for a bad ground, but the rest of my gauges work.

If all else fails, I'm going to go the aftermarket route. Possilby a two or three gauge cluster and also get an aftermarket oil pressure gauge and/or voltage gauge.

 

I experienced eactly what you had going on right after i head my pulled about 3 weeks ago. I put a new temp sending unit and it fixed the problem right away. Out of the two electronic plugs replace the one with the male end to the right.

 

Realized I hadn't fixed this yet. So today I went out and pulled the sensor for the temp gauge out. It had some build up on it, so I took a piece of sand paper and cleaned it up.
Now the temp gauge works like new, I can even watch it and tell when the thermostat opens up. Sorry it took so long to get ya'll the remedy.

 

When I first got my 87 the temp nor fuel gauge worked. I traced everything back to the cluster. When I pulled my cluster the wiring on the back (paper plastic wire thingy kinda blue in color) had been corroded. I changed mine out and both gauges now work.

 

im currently dealing with a temp gauge problem in my sr5 swap too. with no key in the ignition its at the bottom, it reads about 1/2 way warmed up when i start it, and as it begins to warm up, it slowly rises till it basically pegs out that its overheating. i know its not because the original gauge cluster reads slightly higher than the center of the gauge. its been daily driven for well over 10 years, so i know the new cluster is wrong.

edit-

maybe i found the problem. according to the write up that i read, i assumed they all swapped. i know i got it out of an 86 sr7, and mine is an 89.

 

Sounds like the ever typical temp guage overshoot. Go ahead and do a thread search on temp guage overshoot. Thats where i found my info at. That is if im assuming correct? im taking it as it pegs out, then levels back to normal as you continue to drive.

 

Nope. Stays pegged out the entire time.

 

when that happened to mine I replaced the temp sending unit next to the thermostat. cost 12 bucks and I've had no problems since.

 

I will have to try that.