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gcleeton

TWO Legacies wouldn't start!

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Hello

It's been pretty cold here in the snow in NY State so I put my 2 Legacy Wagons 96 and 99 in the garage and put the gas heater on overnight.

Next morning neither of them would start until I left them out in the cold.

Why please?

Gil (newbie to USA from UK!)

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That is strange. Only thing I can think of is some kind of "vapor lock" from warming them up after being outside in the cold???

 

Weird. If it happens again, try releasing the gas cap to see if there is pressure built up.

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I don't think vapor lock is a problem on F.I. autos, what with the pressure the fuel system is under.

 

Do you mean they wouldn't crank, or they were cranking and wouldn't fire?

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WOW, this has got to take some kind of prize as the weirdest problem. In my over 40 years of working on cars, I have never heard anything like this. There has got to be a simple explaination. So you drove them into the garage, what did you do then? In the morning (or whenever), when you went to start them, what exactly did you do? How did you get them out in the cold again?

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It was a cold day.

When i returned from trips out I drove them into the garage and left them overnight with the gas heater on and doors closed.

The next morning both of them would crank but not start.

I pushed them outside for half an hour and they started first touch as usual.

Gil

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I think there was a Car Talk Puzzler similar to this: Some cars were stuck in traffic due to a smokey field fire. When the traffic was allowed to go the cars with the oxygen sensors wouldn't start. I just guessed that was the answer, I never checked.

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I think there was a Car Talk Puzzler similar to this: Some cars were stuck in traffic due to a smokey field fire. When the traffic was allowed to go the cars with the oxygen sensors wouldn't start. I just guessed that was the answer, I never checked.

I was WRONG!!! I just went to the Car Talk website and I was WRONG, Wrong. wrong. I guess I don't know why your cars don't start either. Maybe the tire presure is low, that sounds about as good as my last guess.

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That is really a wierd problem, I can't think of anything that would cause that, it just doesn't make any sense. If there was enough oxygen for you to breath while trying to start the cars, there was enough to run the engines.

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The answer is really very simple: the cars simply did not want to leave their warm resting place on a cold morning. I don't blame them, I also prefer to stay in my warm bed in the morning. :rolleyes:

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Here is my theory: Coolant temperature sensor and lack of Intake Air Temperature sensor.

 

Coolant temperature sensor. Keeping the car inside makes the computer think temperature outside is 60F - or what ever in your garage. So computer would plan for a 60F cold start and send limited fuel. You must have opened the garage door to start and get the car out - that let in a lot of cold air. The incoming air is much colder and computer isn't sending enough fuel, since coolant is at 60F.When you put the car out, engine coolant gets cold, computer senses it, and sends enough fuel.

 

I can't find Subaru Intake Air Temperature Sensor on a Subaru, that would explain it too...

 

It is possible the problem is entirely something different and not related to car being in warm/cold setting. The act of pushing the car out from garage could have done something. The act of cranking the engine a few times might have done something - may be they would have started inside the garage later too...

 

Is this the first time you took the car into garage and put the heater? Any previous history?

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I am not sure whether Mass Airflow Sensor in Subarus somehow figures out Intake Air Temp through air mass - colder air would be heavy. I understand some MAF have a built in Intake Air Temp sensor. In either case, I suspect big differences in air/engine temp might have thrown off the computer, not sending enough fuel.

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Seems like the lack of oxygen would also effect the heater and the set of lungs that were both present.

I've seen fuel injected aircraft engines with vapor lock caused by heat soaking.

However, since you are recently from the UK, maybe you just got in the wrong seat through habit and put the key in the glovecompartment lock!

Let us know what you find out.

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Put the cars in the garage without the heater. I bet they start right up. It would not take all that much to throw off a current lean burning FI engine.

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Both of the cars will start if the gas heater is off.

They won't start if the heater is on.

The garage is very damp when heater is on melting the ice.

Are Legacies susceptible to damp?

Gil

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My 90 Leg would not start in the damp, I am in PA. I spent ALOT of time trying to find out why, even to the point of unwrapping the wire harness looking for bare wires. When it is damp and not starting do your fans come on? My problem was that when it was damp something told the car that it was warm/hot when is wasn't. Sent the wrong gas mixture?

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My 90 Leg would not start in the damp, I am in PA. I spent ALOT of time trying to find out why, even to the point of unwrapping the wire harness looking for bare wires. When it is damp and not starting do your fans come on? My problem was that when it was damp something told the car that it was warm/hot when is wasn't. Sent the wrong gas mixture?
Did you test the coolant temp sensor connector and circuit? It would be a likely culprit.

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Never heard of dampness being a problem, if it were, there wouldn't be any Legacys in the Pacific Northwest, noted for it's large amounts of rain.

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I ONLY had the problem in the rain or a REALY damp/foggy type day.

Changed the ECU without results. The ECU I took out worked in the doner car.

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