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HELP! 78 Brat won's Smog


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Well I just took my 78 Brat 1600 to get smogged today, but she failed. Where I failed at was HC ppm. I'm running 3710 at idle and the limit is only 500. I don't even know where to start. This is my first vintage Subaru and I couldn’t even find the PCV valve on it. Please help. I love this car and I need to get it legal!

 

Thanks,

 

17smog.jpg

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WOW! That's totally off the scale. Even 500 is insanely high - around here 220 ppm is the limit, and even when I failed because of a vacuum leak that caused an idle miss, I was only at 350...

 

Over 3,700?!?!? OMG - it's got to be running on two cylinders or something..... run a compression check.... quick!

 

Clogged air filter? Dirty oil? Nasty, nasty carb? Vacuum leaks up the yang? Got to be something, but with a number that high I would check your compression before I did anything else.

 

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Uh oh, now you got me worried. It runs great, plenty of power and smooth idle. I was told it blows some blue smoke when climbing hills, not a smoke screen or anything just a little bit. I just changed the oil and air filter, it has a new carb on it with only a few thousand miles. Wonder if the previous owner screwed up the carb somehow

 

I'll run a compression check tonight. Wonder if the smog machine is whack-o or something?

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the PCV valve on the EA71 is on the intake. If you follow the line that goes from the valve cover on the driver side up, it'll come into a tee right above the intake where it will go into the air filter and into the intake. Where that line goes into the intake is where the PCV valve is. It is about 2" high and threads into the intake....I love having no emissions to pass:D

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Well - blue smoke would be oil burning, and from what I've read, the machines don't look for the type of HC that would produce, so I think you are safe there. Here they also do a "visible exhuast" test (ie - they look at it).... But the oil smoke could indicate some bad rings or valve stem seals, which could also cause a low compression condition, and at low RPM's that can cause incomplete burning of the fuel.

 

Do you even have a cat? A cat and a working air injection system will go a long way to lowering your emmissions.

 

Check the timing also - it might be too far advanced..... and check the routing of the vacuum advance on the disty - if it is hooked up to manifold vacuum, you will get WAY too much advance at idle, and it will throw you readings off... generally speaking you want less advance for less emmissions.

 

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While you're at it check the vacuum advance unit also, altho that shouldn't be a problem at idle unless it's always advanced. Make sure you're firing on all four cylinders--put a timing light pickup on each ignition wire. I've had a car run on only two cylinders at idle and once off idle the other two cylinders would start to fire and the car ran just fine.

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While you're at it check the vacuum advance unit also, altho that shouldn't be a problem at idle unless it's always advanced. Make sure you're firing on all four cylinders--put a timing light pickup on each ignition wire. I've had a car run on only two cylinders at idle and once off idle the other two cylinders would start to fire and the car ran just fine.

Yeah - I bet if it were running on two cylinders, and you had the disty advance hooked to manifold vacuum it would actually seem to run pretty smooth.... LOL. Could explain the smoke too - bad rings = low compression = no fire at idle = need more advance to run smooth.... crazy.

 

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OK, since I know it's unburned fuel that’s causing my problem… I need to know why that fuel is not being burned. A few things I noticed,

1. I smell a strong odor of gas while driving under heavy load.

2. I have a aftermarket ignition. It's just dangling by the wires on the steering column. Could that be causing the misfire?

Everything else checks out on the car. Good compression, wires, cap, plugs, pcv and no vacuum leaks. HELP!!!! :banghead:

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