98LGT running very cold, below the (C) help!

Sorry if this has been answered I searched and searched, but couldnt find this problem on here...

 

On the highway my temperature gauge is below the cold © mark as if the car isnt warm at all, when im in town, it rises back up to normal temperature. I know this is killing my MPG, but Im not sure what the problem is, the temp has never gone over the halfway mark even in the summer. Im in southern Ontario, and the temperature outside is around the freezing mark now, The rad was recently replaced, and going under the car, it looks like one of the headgaskets have been replaced, I just got it this summer, so i dont know too much about the car. It seems to have a bit of a hesitation in first (automatic trans) but picks up pretty good after...

 

Also, A few times the att oil temp light kept flashing after the car was started maybe for 5 seconds the turned off?

 

Any ideas as to what to look for, or if this is damaging anything running so cold, would be awesome!

It sounds like your thermostat is stuck open.

You can check it by pulling it out, but you will have to refill your coolant. If you are laying under the car and looking up at the radiator, it is on the left side behind the radiator. I think it is held on by two bolts. Just watch your eyes, because when loosen the bolts, all of the coolant will drain out. It isn't an expensive part. They carry it at all the auto part shops, just make sure you get the right temperature.

Good luck.

Could be the temp sensor for you gauge is bad. There are two of them, one for the gauge (one wire) and one for the ECU (two wire). If you have a code reader with live data you can read the temp data and see what the ECU is reading. Or like other said it could be a stuck open thermostat. Make sure you ONLY buy an OEM subaru thermostat.

Thanks Guys, I'll check these things out, I read on a impreza 2.5 forum that the thermostat on the Subbies is designed to fail in the open position, which allows the coolant to free flow so that the car wont over heat,unlike my old Ford POS. I'm guessing/hoping thats the issue cause it seems like a pretty easy fix, I'm a little nervous to start messing with wiring, but I think a code reader would be a good investment, seeing as I found one for around the same price as an hours labor at the dealership...

 

Gotta wait until monday when the parts department at Subaru opens, then ill get a thermostat and some coolant and conditioner, hopefully that fixes it... thanks again guys!

+1, what he said.

Thanks for the suggestions, Im going to get in there tomorrow evening, as its now my DD, and meter reading mule, Im hoping the thermostats in there, and its just stuck/dead, but if its a temp sensor, where would I locate them? I'll try and post some pics on what I find under there for anyone thats interested.

Temp sensor or stuck open / missing thermostat

 

If the thermostat is missing, it may be be because its being used to cover up overheating from head gasket problems from the previous owner.

 

You were exactly right, once I took a close look, noticed blue gasket seal around the elbow connecting the coolant tube to the block, and of course when I pulled it off, no thermostat c:spin: So I cleaned it up, put in the new thermostat filled er up with coolant and half way threw burping the coolant back in it start pissin coolant from the connection, like a meat head I gave it a couple more good turns on the bolt thinking I didnt have it tight enough, and snap!! Back to Subaru tomorrow morn to get some new bolts..... I must have knocked the seal loose while fitting it together, think im going use some gasket seal like the last moron who slapped it together with a new rad, crappy green coolant and no thermostat...cant believe it!! Hope its just a lazy m-fer and not a head gasket:eek:

Ohhh awkward

Did you get a thermostat gasket also?

Yep, got the gasket, its a pretty loose fit in the block, so Im guessing I just bumped it while connecting the plastic elbow and thermostat, and squished it a bit and didnt get a good seal. Picked up the bolts this morn, the old broken one had enough left thankfully to get some needle nose vise grips on it and it came out easy, a lot easier then my broken brake bracket bolt when I changed the brake pads. Round two....fight!!

The thermostat should sit in the grove on the water pump pretty snug, aka if wont fall when just sitting there without the plastic part bolted on.

Thanks subikid90, I realized Im a total tool and was doing it wrong, who knew the gasket fit around the thermostat, duh, I had the gasket then the thermostat, no wonder it didnt seal, I read that the little jiggle pin faces the front of the car, but Id better ask you before I button it up, seeing as Im a total hack....

Well got everything back together, filled up coolant, no leaks, burped it, temperature stayed normal during all the revs UNTIL... 2. problems...

 

1. cooling fans never came on, even after a long time... so I took it for a test drive....

 

2. seemed good until the first stop light, then Temperature Hit the Roof:spin: pulled into parking lot let it cool, barely got it home with out seriously overheating....

 

What do you guys think??? Is it my Head Gaskets? heres a couple pics from underneath, passenger side looks new, drivers side looks rusty as hell, and splitting... could it be just the fan not kicking on, remember there was no thermostat when I opened it up...help!!

Headgaskets! (I think)

The PO definitely removed the the thermostat to prevent the car from overheating with a blown headgasket.

 

This is the way I understand it:

With a blown headgasket, exhaust gas escapes the cylinder and enters the cooling system. When the thermostat closes, the exhaust gas builds up against the thermostat. The gas isn't hot enough to open the thermostat, so the thermostat stay closed, causing the engine to overheat. Therefore, with the thermostat removed, the engine won't overheat. The car won't overheat at idle, because there isn't enough exhaust gas in the cooling system to back up against the thermostat.

The way to test if it is the headgasket is to remove the radiator cap, fill the coolant up to the edge of the radiator cap opening, start the car and allow it to warm up to normal operating temperature. Then slowly rev the engine and watch for bubbles in the coolant.

A more definite way to test is to test the coolant for the presence of hydrocarbons (stuff in exhaust gas).

Other symptoms are oil in the coolant, coolant in the oil, and white smoke from the exhaust.

 

Hoping (on the off chance) it is not the headgaskets, did you properly bleed the coolant? Do you feel hot air from the vent when the car is at normal operating temperature?

 

I went through this suck too. I was driving on I25 to Denver when the AC stopped working, I looked down and saw the temp needle pegged to the top. I pulled over and coolant was bubbling out into the overflow tank, which made absolutely no sense at the time. I limped to the nearest autozone, where the cashier assured me it was the thermostat...sure I limped another 10 miles to Denver where I went to 24 hour auto repair. We changed the thermostat, drove it around a bit, and it still overheated. So then we removed the thermostat, I paid a ridiculous amount of money for an hour of work, and drove home. I couldn't figure out what was wrong for the life of me, and then I discovered legacygt forums.

Ya, when Idling in the garage I was getting heat, and even at the begging of the test drive there was heat, but as the temperature gauge went up the heat went down, I tried blasting it to cool the car down, as this worked for my old ford escort, but didnt seam to help.

I'm pretty sure I bleed the coolant well, I did the rev to 2200 4 times and topped up the coolant each time, i let it cool down each time, but the last time when I opened the rad cap the coolant really shot out at me, even though it was cold, and I did notice some steam/smoke coming from the water pump area before I took it for the test drive, but I figured it was just burning up some spilled coolant from when it shot out. But your gas build up explanation would give me reason to believe Im into a head gasket job...

That makes sense. When the temperature went up, the thermostat was closed, so no hot coolant was passing through the heating core, so no hot air.

Do the radiator bubble test and see what happens.

Do a compression check or hydrocarbon test. It will give you a solid answer

Check the dipstick for a gel mixed w/ the oil.

Also run the car and walk to the rear of it, and see if you can smell coolant coming out of the muffler (white smoke).

My leggy had the same issues, If your moving temp goes down, but sitting it climbs (<--- damn that word looks weird) ANYWAYS, Turned out i had a blown Rad fan fuse (20A). that fixed my problem.

Well here's the update, in the middle of a massive tear-down to do the head gaskets, very little pics, but I'm finally in the passenger side looking at the camshafts!! This side was recently done, by the other loser who buttoned it up with no thermostat and screwed me, so i figured Id redo his job since the $320 felpro kit came with both sides, I know I know, use oem, but thats the reason Im in here in the first place:p, so Ill take my chances!!

I was wondering there for a second, and rethinking the advice from you if all you could see in the picture was that I took off the valve cover, I mean damn, that took two minutes. The cam gears were a b*tch but got them without breaking them. I'm not going to pull the engine, just jack it up..., so In my opinion 30% lol