[Pegasuz73]

Hi forum.
Since I brought my new car up here to the sub zero temperatures it is not very willing to start after sitting over night. At about 10 degr below zero (Celsius) it pretty much wont start unless I work the starter for a loooong time. After the first start it starts fine rest of the day even if I let it sit for a couple of hours. Another symptom is an average fuel consumption of 1,5 litres/10k!
After reading all the cold start threads and a couple of other searches it seems likely to be a sensor problem. One of these two: Coolant temperature sensor or Intake air temperature sensor.
I visited the Subaru dealer today and the Coolant temp sensor is 50 bucks and the air temp sensor is about ten times that.
Next week I am having the car hooked up to a diagnosis computer. Hopefully it will show what is at fault.
Anybody having any thoughts on this on the 2005 3.0R?

 

[1 Lucky Texan]

one thing that could happen when a car sits for hours, is loss of fuel pressure in the fuel rails. Next cold start, you could try turning the key to ON without starting, wait several seconds while the fuel pump runs. It will stop. Turn the key to OFF, then repeat a few times, waiting 4-5 seconds each time you switch to ON. After a few cycles, THEN start the car. If it is improved, there may be a leaking injector or some other problem with holding fuel pressure.

 

[Pegasuz73]

Thanks Texan. I will try this tomorow.

 

[1 Lucky Texan]

there were also some year/model Subarus that had fuel leakage problems when cold. I don't recall any symptom other than smell - but worth investigating if for no other reason than safety.

If the car is being kept in 'choke' conditions by the ECU/bad temp sensor or w'ever, I suppose it is also possible, when shut down, that the xtra fuel in the cylinders is washing-down oil and causing low compression. It's a longshot but, a mechanic might be able to check compression if the car fails to respond to other tests and is left overnight at the shop.

 

[Pegasuz73]

I think this is solved...
I had my mechanic pull the plugs and go go the bottom of this. Evidence :
The car takes way to much fuel
The car is hard to start when it is cold.
It wanders a little at idle.
I found an empty Flash lube bottle mounted under the Hood.
3 cylinders om one side is low on comp. Only 9-11.
Subaru workshop /dealer in Stockholm sais that they hardly ever have any problems like this with the H6. Except when it has ran on E85 (etanol fuel) that kills the valve setts.

So..... Jag everything indicates that my car has been fed wrong fuel in italy and is worn out in the valve seats on one side.

This Will get expensive.....

Any thougths on this?

 

[1 Lucky Texan]

one bank low 'feels' like a slipped cam pulley.

odd

 

[Pegasuz73]

Could you please expand on that for me. I´m not a pro mechanic. Maybe I can point my mechanic in the right direction.

/C

 

[Pegasuz73]

I thought since it is a timing chain on this engine that it was allmost impossible for the chain to slip and get out of timing. Have I got it all wrong ? Is it a belt and not a chain....

 

[1 Lucky Texan]

I thought since it is a timing chain on this engine that it was allmost impossible for the chain to slip and get out of timing. Have I got it all wrong ? Is it a belt and not a chain....

it is a chain and it would be quite odd to have a failure like that. Just seems almost too coincidental to have bad valve seats on one bank. Not impossible I guess.

the chain cover at the front will have to come off anyway if they plan to remove the head(s) so, we should find out as they dig into it.

 

[Pegasuz73]

Yes this is very odd. My mechanic is very competent and usually knows what he is talking abaout.
When I picked the car up yesterday he showed me some things he found that made him suspicious that the engine has been tampered with. On the side with low comp there are a few screws missing here and there. Nothing major. One holds the cover over the manifold, one holds a hose bracket and so on... Ha is starting to belive that something has been fiddled with...

I want to be prety sure what is wrong before we start tearing the engine apart. Once that is started the money is rolling.....
Any input on theis is appreciated.

 

[cardoc]

A few questions:

Does the car run odd after it starts?

Does the car have low power output?

Is the MIL/CEL light on?

Where and what kind of fuel do you use? Is it a high blend ethanol? (high alcohol content causes long cold start issues due to necessity of volume for combustion)

Yours has variable valve control. And a failed system will effect one side. The "odd" side, bank 2.

 

[Pegasuz73]

A few questions:

Does the car run odd after it starts?

Does the car have low power output?

Is the MIL/CEL light on?

Where and what kind of fuel do you use? Is it a high blend ethanol? (high alcohol content causes long cold start issues due to necessity of volume for combustion)

Yours has variable valve control. And a failed system will effect one side. The "odd" side, bank 2.

It only has start trouble when it is below freezing out. otherwise it cranks on 2 turns or so. Once it is started it runs fine.. allmost, it has a slight dip in the idling every now and then. It is hardly noticable but it idles a little rough.

The car isn´t benched or anything so I don't have any numbers on the power output but it feels like it runs very good and puts out lots of power when I floor it. I can't feel anything missing there (bare in mind that this is the only H6 I have driven)

No engine lights or warning lights. The car has been diagnosed with the odb2 connection by the mechanic, and no error codes or faults show up.

I onnly run the car on 95 oct petrol. But we found an empty bottle installation of this under the hood Flashlube Automatic Lubrication Kit: Flashlube fuel additives Synthetic lubricants for the automotive industry - Genuine Flashlube?
So we are suspicious that the italian owner has ran it on something else.

 

[cardoc]

Check fuel pressure, oil level, clean the throttle body and PCV valves. What condition are the plugs in and are they the proper plug? NGK heat range 6 is what is called for it. And check with the station you buy your fuel from on the alcohol blend. If its over 10%, its going to start hard in cold weather, but will start fine after you've driven it as the engine block retains some heat and will help it combust.

I would assume that maybe the previous owner may have added your mystery fluid to the transmission so you may want to flush that out good while your at it. Or it was added to the fuel as a stabilizer/treatment like Marvel Mystery Oil or Lucas. If it runs smooth, its not a compression issue. Its something simple that is being overlooked.

 

[Pegasuz73]

Check fuel pressure, oil level, clean the throttle body and PCV valves. What condition are the plugs in and are they the proper plug? NGK heat range 6 is what is called for it. And check with the station you buy your fuel from on the alcohol blend. If its over 10%, its going to start hard in cold weather, but will start fine after you've driven it as the engine block retains some heat and will help it combust.

I would assume that maybe the previous owner may have added your mystery fluid to the transmission so you may want to flush that out good while your at it. Or it was added to the fuel as a stabilizer/treatment like Marvel Mystery Oil or Lucas. If it runs smooth, its not a compression issue. Its something simple that is being overlooked.

I really apreciate you input on this. I hope I don´t have to tear the engine apart.
We just changed the plug to what the specs calls for.
The flashlube bottle hose was hooked up to the intake to have it mixed with the fuel vapors. So it wasn´t going in to the transmission.

What are your thoughts on the fuel-consumption. It takes allmost 1,4 liters/10km when softly driven city and highway.? Don´t you think that this and the low comp on one side is associated?

 

[cardoc]

The fuel consumption is a bit high. If it has been running rich for a long period of time, carbon build up in the intake, on the valves and in the exhaust (Catalytic Converters) will cause poor fuel economy.

I would try the throttle and intake cleaning, clean the PCV valve and see if there is improvement. Front AF sensors may be sending improper ratio data to the ECM without triggering a CEL causing a rich condition. The AF sensors do not effect the cold start issue but do have a lot to do with how the ECM calculates its fuel trim.

Also, is the thermostat operating proper? The engine temperature should average about 200F/95C. Temperature is vital to engine combustion and will effect fuel consumption.