bdmartin

GD,

Now that I've passed emissions, is it possible and/or desireable to block that air injection system? Lots of backfiring still.

Thanks for all your help. It passed with flying colors this time.

Rick,

I have replaced the front exhaust/catalytic converter with a magnaflow direct fit. As you suspected, my old one was pretty well burned out, with chunks of the honeycomb falling out when I removed it. Now it's rather LOUD and backfires quite a bit, but it seems to run better on the road. I plan on mixing in some denatured alcohol, as you've suggested, before I have it emmissions tested again. It still has some E85 gas mixed with regular unleaded in it, about 3-4 gal each. Is there anything else I can adjust to lean it out, and how far should I retard the timing when I do have it tested? Also, I've seen contradicting info online about the idle mixture screw. Is it clockwise leans out the mix, or the reverse? Thanks again for your help.

Brad

Rick,

Thanks for the reply. Is there a possibility that my vacuum system is the cause of my problem? The reason I ask is that my car only has 105K original miles, and the entire exhaust system appears original and in excellent condition for a 27 year old car. Very little rust and no holes. There's no O2 sensor, ECC or EGI on this model. I have no problem replacing the cat, but I'm less than confidant that my vacuum system is 100% correct. Are there any comprehensive diagrams or pix showing where the lines go? Also, what mixture of Dentatured Alcohol/ fuel should I use, and is E85 fuel ok?

Thanks again for your time and expertise.

Brad

P.S. sorry for posting more than once, having trouble uploading message.

GeneralDisorder,

From reading your posts you seem to be quite well versed in all things Subaru. I'd like to ask your advice on my car. I have an 84 GL 4X4 Hatchback, 1800 ea81 with a hitachi 2-barrel. I just got it running after having the heads rebuilt, and rebuilding the carb myself. It seems to run well but failed emmissions due to high HC (4.48GPM / limit 3.0) and CO (39.32GPM / limit 30.0) readings. After draining the gas and replacing with E85 fuel it failed the retest as well. The readings were: HC - 11.729 (more than twice the first test) and CO - 3.026 (36GPM dropoff and well below limit) Apparently I still have to much unburned fuel. As far as I've read the only adjustment is the idle air/fuel mixture. Can u offer any advice on what I might look for to get the HC readings down? Any help would be greatly appreciated. Thanks, Brad

GeneralDisorder,

From reading your posts you seem to be quite well versed in all things Subaru. I'd like to ask your advice on my car. I have an 84 GL 4X4 Hatchback, 1800 ea81 with a hitachi 2-barrel. I just got it running after having the heads rebuilt, and rebuilding the carb myself. It seems to run well but failed emmissions due to high HC (4.48GPM / limit 3.0) and CO (39.32GPM / limit 30.0) readings. After draining the gas and replacing with E85 fuel it failed the retest as well. The readings were: HC - 11.729 (more than twice the first test) and CO - 3.026 (36GPM dropoff and well below limit) Apparently I still have to much unburned fuel. As far as I've read the only adjustment is the idle air/fuel mixture. Can u offer any advice on what I might look for to get the HC readings down? Any help would be greatly appreciated. Thanks, Brad