Engine Temperature Sensor - How hard is it?

[subby95]

I have a 1995 Subaru legacy that has seen better days.... It has 158,000 miles on it and has been having problems starting lately, especially when I have just driven it a short distance and only turned it off for a few minutes (like at the gas station). It's been a rough year for this subie.

 

Early in 2006, it wouldn't start and I realized the battery was toast, so I replaced that. Then the gas mileage plummeted and it was running really rough. The check engine light came on intermintently and then permanently. I coughed up $25 at the local gas station to have them read the computer codes - which said to the check the engine temperature sensor. They cleared the code and said to drive it for a little bit to see if it came back on. Very quickly after that, my pulleys went crazy - there is no other way to describe it - all the belts were off and the pulley's were all over the place. I took it into a shop that I had never been to but that a co-worker has gone to for almost 20 years. They told me that the crankshaft had been damaged, so they weren't sure what they'd be able to do. Luckily they were able to put it all back together regrinding the key rather than welding it all together. It has been several months since that repair and everything seems to be ok.... except my check engine light is back and it's having starting problems.

 

At first I thought maybe just the fuel filter needed to be replaced, but then I remembered the engine temp sensor and thought that might have something to do with it.

 

My car also has transmission problems which will probably be in the 300 range if I'm lucky. So I am trying to prioratize my repairs to keep the car functional but not a money pit.

 

I feel confident that I can replace the fuel filter but I can't figure out where the engine temp sensor is and how realistic it is for me to try and do it myself. I am definitely not a skilled mechanic. I don't want to do anything stupid.

 

Any suggestions?

[ericem]

Ok first dont jump to the engine sensor. Start off with the fuel filter, air filter. And go to a local dealer this way they can diagnose the reason why the check engine light is on. But how does the car drive is it smooth start up smooth. If so it might just be the gas cap that has a air leak.

[subby95]

Ok first dont jump to the engine sensor. Start off with the fuel filter, air filter. And go to a local dealer this way they can diagnose the reason why the check engine light is on. But how does the car drive is it smooth start up smooth. If so it might just be the gas cap that has a air leak.

 

I'll do the fuel filter, but when I had the engine worked on earlier this year I also had a tune up and oil change. The spark plugs & wires and air filter were changed out - among other regular maintenance items that I don't remember off the top of my head.

 

I am really hesitant to go to a dealer. I had an extremely bad experience with the subaru dealer here in town and really do not want to repeat it.

 

I don't think the car does runs smooth at all.... especially when I start it up again. There is a lot of gas pedal pumping and once it is started, it really would like to die, I just don't let it.

 

I was thinking the sensor only because that was the previous code that was reported. It does make sense to make sure that's what it still is reporting.... I also did some reading a it sounded like that could cause the starting problem I am having.

 

When they do an emissions test, don't they test for air leaks on the gas cap? I only ask because I just had one done recently, granted before this problem arose, but thought they checked that kind of thing.

 

Also probably of importance is that the problem started on a really hot day when I had to drive it pretty hard on steep hills in city traffic.... then it continued as our heat wave continued. It does seem to be happening less often when it is cooler outside.

[ericem]

Ya i doubt the temp sensor. I love my dealer. But i remember one dealer i hate them. I only go to dealers acually owned by subaru. ANd that looks nice(lol). I suggest another dealer. I just preffer the dealer just because they only work with subarus. ANd i have the worst luck with mech. shops. They dont know what there looking at. These cars arent built like a GM or ford or chrysler there built complex. But if u dont mind waiting for someone to reply u may. Im sure someone will say a knock sensor O2 sensor theres are thousands of sensors in your car. Oh and i dont know if they test air leaks. But i doubt it. All they do is stick a hose up ur muffler(my interpretation).

[edrach]

Temp sensor is a common failure item on the early EJ22s. Turns out there are two of them; one reports to the temp guage and that's okay. The other reports to the ECU and apparently sets the fuel mixture. Code 35 if I remember correctly. It is under the Idle Air Control assembly and has a brown connector with two wires coming out of it. Having replaced two of them in the last year I can tell you it is a pain to unplug and remove/replace. But it's do-able; just needs patience and perserverance and less than 30 minutes. Oddly enough, when I replaced mine the other 4 codes it was throwing went away also. You might try Legacy777 on the Legacy Central board (and our USMB); he's the resident expert on early EJ's.

[porcupine73]

A lot of auto parts places (like auto zone) will read the codes for free (hoping you'll buy the parts to fix it from them). Make sure you write down any codes they find. If you don't know what they mean post on here and I'm sure someone will tell you or do a google search. Without reading the codes and knowing what general system(s) is/are having problem(s) it can become costly to just throw parts/sensors at it. Regular maintenance such as fuel and air filter should be done in any case.

 

The fuel filter is pretty easy to change; hose pliers can help as the hoses seem to adhere to the barbs pretty tightly sometimes. Also might want a pack of new fuel hose clamps in case you strip out the screws on the existing ones. If you do the air filter make sure that all hoses (that might inadvertently disconnect while doing the job) are reattached.

 

Your belts all falling off and the crank damage issue sounds like your crankshaft pulley bolt loosened up, thus letting the crank pulley move out and tilt. This can happen especially if the timing belt is replaced (or for whatever reason the crank pulley was removed) and the bolt wasn't retightened properly. It can result in a hogged out keyway on the crankshaft which can require crankshaft replacement, but it sounds like they were able to fix yours. Louis

[subby95]

Thanks for the tips - I will replace the fuel filter and try to find someone to read the codes for me.

 

Ironically, the crankshaft issue I had was the second time my pulleys went nuts. The first time it happened, my alternator actually went out and that's the first time I have ever taken my car to a dealer. They were extremely nice and helpful and my belts & pulleys looked great when they were done. So when I needed my brakes done I went back to them and they WOULDN'T do it. They said I had plenty of life on my brakes but I needed a new transmission.....

 

I have driven many a car until it has no brakes - let's just say I learned the hard way and put my dad through much strife in the process - so I am very confident in my knowledge that the brakes need work/maintenance.

 

I took it to another shop, after market, and they did a complete brake job and actually said I was driving a rather dangerous car given the condition of my brakes. I also did some research on the transmission issue. It was something called torque bind and while it is clearly an issue with these cars - there seem to be ways to fix it besides a whole new transmission.

 

In the end, I felt like that dealership was trying to sell me something that I may or may not need and wouldn't do work that was clearly needed. They claimed that no one else knows how to work on Subaru's but I was talking to aftermarket shops that work only or predominantly on subarus! I don't know what I would have done if the recent shop couldn't find a fix for my crankshaft problem because it was that dealer shop who was last to take apart anything in the front end of my engine and I know I wouldn't get anything out of them!

[Olnick]

. . . have them read the computer codes - which said to the check the engine temperature sensor.

 

And, since that's what the code said that's the very first thing you should do. Can make a tremendous difference in your engine's operation. IIRC our '95 Legacies have just one temp sensor--it talks to the computer then the computer tells the temp gauge what to read.

 

Yes, it's a bit of a pain to get to but it is doable. Get a Haynes manual to point you in the right direction. Try to find a friend who has some wrenching ability. Go to an independent shop if you have to. Ask questions here.

 

But by all means replace the coolant temperature sensor. It's $30 well spent.

 

Good luck.

[croak]

I had similar problems w/ an 87 ford (POS), the temp sensor went out and it refused to start. it sounds like your having verry similar problems. i know it wasn't a subaru but i assume the Engine temp sensor does esentialy the same thing, ajusts the air fuel mixture dependant on engine temp.