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leaking HG cylinder #3..smell gas under hood


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Just yesterday I bought an 01 OBW but didn't look at it long enough.  There is a slight/moderate smell of gas under the under and can't find a gas leak.  I did notice the back of the engine, on cal. #3 there is a good leak, looks like oil and coolant.  

 

The seller told me the HG had been done...

 

but I guess this is a sign the HG need to be done again correct?

 

Could a HG leak have some gas in it?  I scraped the ooze down near the leak and I could smell gas.

 

The coolant level was just less than a cup low.

 

Dip stick looks good.

 

There is a p0420pd code, all monitors clear except caty.

 

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the residual oil/coolant may be from years ago and the HG are fine.

 

gas smell is likely a loose line somewhere or exhaust leak.  exhaust leaks routinely cause the 0420 catalyst inefficiency code.

 

what brand headgaskets were used when it was repaired and were the heads resurfaced?

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thanks Gary,  

 

The leak is fresh and wet though.
 

I haven't got the maintenence records yet from the seller.  

 

There is an exhaust leak at the junction past the two caty's.

 

The leak is fresh and wet though.

 

With out a garage I need to wait till 30's weather.  But looking forward to working on this.  If it need HGs, should I tackle this after some tutorial videos?  I did my timing belt for the first time two weeks ago on another suby.  

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The common issue for fuel smell on these cars is the fuel line clamps on the fuel rails under the intake manifold. There are some hidden ones hard to get one, tighten them all up and see if that fixes the fuel leak smell.

 

You can run for quite some time with an external headgasket leak. Just make sure you don't run out of coolant and it's fine. It'll definitely get you until warmer weather, besides tightening the fuel lines I wouldn't touch the headgaskets.

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Take a good sniff at the dipstick, away from the car itself. If the oil smells "gassy",  you may have fuel wash, gas getting into the oil from a "run rich" condition.  This thins out the the oil and can cause significant damage to the bearings and everything else that is oil lubricated.

 

This can be caused by a dirty Mass Air Flow Sensor, failing knock sensor, bad coolant temperature sensor on the coolant crossover pipe as well as a failing injector or o-ring.  Cold weather brings out the worst in our cars' fuel systems!

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Yea, it's in the cold when subarus have the issue with the loose fuel lines. If you google it you'll find a lot of info on it.

 

Also before condemning the headgaskets, there is a small coolant hose that runs from the passenger side of the engine up to the throttle body, and from the throttle body back to the coolant crossover. Get a flashlight and a mirror and make sure that hose isn't leaking. 

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The common issue for fuel smell on these cars is the fuel line clamps on the fuel rails under the intake manifold. There are some hidden ones hard to get one, tighten them all up and see if that fixes the fuel leak smell.

 

You can run for quite some time with an external headgasket leak. Just make sure you don't run out of coolant and it's fine. It'll definitely get you until warmer weather, besides tightening the fuel lines I wouldn't touch the headgaskets.

oh yes you can ive been running my bmw with an external hg leak for about a year and a half now thogh it is slowly getting worst. a good friend of mine has a 2002 obw and his hg has been leaking externally since he bought it 2 years ago. my mom has i tihnk it was an 04 or 05 obw same deal leaking oil form hg externally its been like that for at least 3 years.

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Normally the MAF is mounted on the filter box on the passenger side.

If it has a MAF the split in the bolt will cause it to read low which will lean the A/F mixture at idle.

 

Wrap the boot in electrical tape for a temporary fix. Also it will help to twist the plastic part upward some so the boot sits naturally.

 

And I'm pretty sure there is supposed to be a hose clamp where those two plastic sections meet.

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  • 4 weeks later...

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