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98 Legacy wont start, Thinks its 400 degrees!


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The daughter calls and said the Legacy GT wagon will not start. It wants to start. It almost catches but will not run.

 

So I go over there and turn on the key. The first thing is the fan goes on.

 

I pull some codes and there are 2 both having to do with the temp sensor. That sort of explains the fan.

 

I go through the scanner to see what the engine sees. For some reason it thinks the engine temp is 400 degrees F.

 

Would that cause it not to start? I plan on replacing the temp sensor tomorrow. Where the heck is it?

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[...]I go through the scanner to see what the engine sees. For some reason it thinks the engine temp is 400 degrees F.

 

Would that cause it not to start?

If the ECU ''thinks'' the engine is hot, it won't set up the proper conditions (rich mixture, etc.) needed for a cold start.

 

I plan on replacing the temp sensor tomorrow. Where the heck is it?

The engine coolant temp sensor is mounted to the coolant pipe -- follow the upper radiator hose to that metal casting, then look under the intake manifold in the vacinity of the cylinder #3 runner. Unfortunately, it's kind of buried. Be sure you replace the sensor that has two terminals (the one with a single terminal is for the temp gauge).

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What a bear! I finally found it under a wiring harness. I picked the harness apart so I could get to the sensor. The picture is accurate if the harness is not present.

 

Now the bad part. The connector was was fused into a solid mass and broke off of the sensor. I cannot get the rest of the sensor out of the connector.

 

The connector is not available at the parts store so I assume it is a dealer only part.

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Forgive me if I'm being dense here (it's been several years since I changed mine), but:

 

Are you saying the plastic connector on the harness (female, IIRC) fused to the plastic connector part (male?) of the sensor?

 

You should still be able to remove what's left of the sensor with a wrench on the brass head, right?

 

And I doubt you'll be able to get a connector at the dealer--they'll probably tell you you have to buy an entirely new harness! May be best to find a pull-and-pay or salvage yard and get a used one to splice in.

 

Big question is why did they fuse together, electrical short?

 

Good luck.

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I had that happen-connector end of sensor borke off inside harness connector. Remember you will need to releas the latch,it is proably still holding what is left in the harness connector. And you my me able to grab with mini-vise grips(i was able to), or drill a hole and use a self tapping screw to gett ahold of the broken piece. good luk let us know how it works out and if it fixes tha probelm

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Very good. The new sensor has the male end as part of it, right?

 

So if the old connectors are burned/fused together you'll have to find another female end to splice on. I don't know if there is anywhere to buy just the connector, which is why I suggested a salvage yard.

 

Now if the old connectors are just a tight fit and gunked up, I'd use some Liquid Wrench or carb cleaner and try to wiggle them apart with screw driver/needlenose/channel locks.

 

Good luck.

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Well it worked! The connector finally came off using two pairs of vice grips.

 

There was enough of the connector left to put it back and have it clip on.

 

After clearing the codes it started!! It was music to my ears. Thanks folks!

 

I drove home the few blocks and topped off the radiator. I took a gallon of antifreeze mix. I am sure that much did not leak out. Now it over heats and there is no heat coming out of the heater. Just like a bad head gasket!

 

Now what did I do??

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Now it over heats and there is no heat coming out of the heater. Just like a bad head gasket!

 

 

Congrats on the ECTS install . . . but uh-oh! Sounds like classic HG symptom. This is an EJ25 right?

 

Try burping the cooling system (search under "coolant burp") then keep a close eye on coolant level and temperature gauge. If it keeps overheating dont drive it.

 

Good luck.

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[...] Try burping the cooling system (search under ''coolant burp'') then keep a close eye on coolant level and temperature gauge. If it keeps overheating dont drive it.

Yes, if it wasn't overheating previously then it's likely that there's now some air in the system that needs to be bled out.

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Ok. I found why it would not burp. There is a small coolant hose under the manifold. What the heck is that for? I discovered it by squeezing the upper radiator hose and heard a sucking noise. I hooked the hose up and now it burps properly.

 

Now for my next issue. It is kind of embarrassing actually. I cant figure out where all of the hoses go. A few are good guesses.

 

There is a hose from the right cylinder head that I assume connects to a tube under the airbox which goes to s similar hose to teh other cylinder head.

 

I think I figured out where the rubber hose from the silencer goes.

 

Now there is a tube from the block that connects to a T. Where do those hoses go?

 

It is sure heck getting old and having little short term memory..

 

Help!

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Ok. I found why it would not burp. There is a small coolant hose under the manifold. What the heck is that for? I discovered it by squeezing the upper radiator hose and heard a sucking noise. I hooked the hose up and now it burps properly.

 

Now for my next issue. It is kind of embarrassing actually. I cant figure out where all of the hoses go. A few are good guesses.

 

There is a hose from the right cylinder head that I assume connects to a tube under the airbox which goes to s similar hose to teh other cylinder head.

 

I think I figured out where the rubber hose from the silencer goes.

 

Now there is a tube from the block that connects to a T. Where do those hoses go?

 

It is sure heck getting old and having little short term memory..

 

Help!

 

 

post some pics of the hose in question--what it looks like and what it is attached to at the one end

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some of the hoses, emissions, may be posted on the hood. at least one of the right side head hose goes to the PCV valve.

 

do you know any one with a similar year legacy to compare?

 

i always keep an extra one around for just this purpose. :banana:

 

my wife even thinks it is a good idea. she really hates an empty drive way. :eek:

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I thought I had it. Sometimes it is better just to walk away for a while.

 

I think I uploaded the pictures.

 

The first picture I am fairly sure of. That is from the tube from the MAF to the air box. There is one hose that goes to the block. They ar ean inch apart in the picture.

 

In the first and second pictures you can see how the T goes to the block, throttle body and underneath the air box. Below the airbox are two hoses going to each cylinder head.

 

Picture three has a better view.

 

In picture four there is an empty nipple. This actually opens into the air box.

 

I started the car and it will not idle because of the air leak.

 

The diagram on the hood did not help much. And Subarus are not as common as I would like around here so I could look at an example.

 

Let me know if any other views would help.

 

Thanks

 

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Perhaps these pictures would help identify the hoses.

 

The questions are 1) What hoses go to the air box? There is a plastic molded tube that goes under the bow and I believe it connects to long hoses from each cylinder head. There is a T on this that goes to the PCV? There is a blind nipple on the back that is sealed and facing forward of the box that opens into the box.

 

2) What hoses go to the what looks like a T coming from the center of the block? The bottom goes into the block obviously. The one on the side is kind of U shaped and I am not sure where that goes. The top I have connected after the throttle body. Is that correct?

 

Like I said this is kind of embarrassing. :confused::-\

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The two breather hoses should not connect to that same tube under the air box. The one from the left (passenger) side cylinder head goes to the tube that's behind that. The one from the T connects to the tube that crosses over to the right side cylinder head.

 

The one that sticks out of the front of the air box... I'm not sure.

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That's why it's something I am not completely familiar with, I get out some colored tape or masking tape with a marker and mark them before I take them apart. Just a little advice for next time.

Ordinarily that is what I would do like when I remove an engine.. However I disconnected a few other hoses to get the that coolant hose and got in too deep.

 

Does anyone else have a 1998 EJ 25 that can take a look? The questions are where do the hoses go from the air box and where do the hoses go from the T that connects to the block.

 

Thanks!

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Ordinarily that is what I would do like when I remove an engine.. However I disconnected a few other hoses to get the that coolant hose and got in too deep.

 

Does anyone else have a 1998 EJ 25 that can take a look? The questions are where do the hoses go from the air box and where do the hoses go from the T that connects to the block.

 

Thanks!

I've got a 98 legacy obw with a ej 25. I've marked up a couple of your pictures.

 

I'm calling the rubber pieces you can remove hoses, and the connections coming out of the airbox tubes.

 

Hose #1 goes from the y in the pcv system to the tube that I've marked as #1 in the air box.

 

The two hoses in the same picture as tube #1 should stay where they are in that picture.

 

Hoses #2 and #3 don't attach to #1. They go from tube #3 that I've marked in the picture to tube #2, that is on the back side of the airbox -- opposite of where the airbox connects to the throttle body. So yes, hoses #2 and #3 route one tube on the airbox to another tube on the airbox. Don't ask me why.

 

Hope this helps.

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