280+k 90 Legacy Posted September 4, 2011 Share Posted September 4, 2011 I took my car in to get it Smogged today and it didn't pass. The HC was over the limit at idle but everything else passed. Here's the numbers Idle RPM 691 %CO2 13.6 %O2 1.2 HP (PPM) Max 120 GP 270 Measured 324 CO (%) Max 1.00 GP 2.50 Measured 0.70 Not Idle RPM 2560 %CO2 14.0 %O2 0.6 HP (PPM) Max 140 GP 290 Measured 49 CO (%) Max 1.00 GP 2.50 Measured 0.66 I did a major tune-up earlier this year when the car was not running well. I think I remember buying cheap spark plugs and I'm thinking maybe about getting the NG plugs. Not sure this would solve my problem though. From what I've been reading high HC levels mean there is unburnt fuel. I'm currently running 91 octane full. Maybe I should put an additive in there before my test? Thanks for the help. Link to comment Share on other sites More sharing options...
johnceggleston Posted September 4, 2011 Share Posted September 4, 2011 year, model , engine, trans, miles, ???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????/ Link to comment Share on other sites More sharing options...
lostinthe202 Posted September 5, 2011 Share Posted September 5, 2011 Judging your screen name, I'm going to guess that you have a 1990 Legacy with over 280k miles. As for the trans, I'll qualify the next question with the statement that I know nothing about Subs with auto trans. That said, you report 691 rpm at idle during your test, do subarus with an auto bring the rpm that low in park? I dunno, but if not, then a 5 speed. Sorry I can't clarify further on your smog numbers. but some basic questions: Do you have a check engine light? How has your fuel economy been? Noticed any "rotten egg" smell when sitting at idle such as at a stop sign? Will- Link to comment Share on other sites More sharing options...
Nug Posted September 5, 2011 Share Posted September 5, 2011 This is one of those times that a couple of gallons of E85 can work wonders. Link to comment Share on other sites More sharing options...
280+k 90 Legacy Posted September 6, 2011 Author Share Posted September 6, 2011 Hi Everyone, Thanks for your replies. The car is an automatic, 1990 Subaru Legacy with the 2.2L engine. It has 288,000 miles on it and runs great. I get around 25 MPG on a tank or about 300 miles to a tank of gas. No check engine light or codes in the ECU and no rotten egg smell. I pulled the spark plugs and checked the gap this weekend and everything looked ok there. I also put in a can of 'Guaranteed to pass' (a engine/fuel system cleaner) in the fuel. I've been running 91 octane fuel in the car for as long as I can remember. From what I've been reading, HC is caused by unburnt fuel and high octane fuel burns slower than lower octane fuels. So I was thinking after I finish this tank of gas with the 'Guaranteed to pass' stuff putting a few gallons of 87 in it seeing how it runs and if everything checks out trying the test again. As for the E85 I've read about people doing that. Does it really work? Thanks for the help! Link to comment Share on other sites More sharing options...
Rooster2 Posted September 6, 2011 Share Posted September 6, 2011 Hi Everyone, Thanks for your replies. The car is an automatic, 1990 Subaru Legacy with the 2.2L engine. It has 288,000 miles on it and runs great. I get around 25 MPG on a tank or about 300 miles to a tank of gas. No check engine light or codes in the ECU and no rotten egg smell. I pulled the spark plugs and checked the gap this weekend and everything looked ok there. I also put in a can of 'Guaranteed to pass' (a engine/fuel system cleaner) in the fuel. I've been running 91 octane fuel in the car for as long as I can remember. From what I've been reading, HC is caused by unburnt fuel and high octane fuel burns slower than lower octane fuels. So I was thinking after I finish this tank of gas with the 'Guaranteed to pass' stuff putting a few gallons of 87 in it seeing how it runs and if everything checks out trying the test again. As for the E85 I've read about people doing that. Does it really work? Thanks for the help! I am thinking that the "Guaranteed to pass" additive product is mostly E85 with some Seafoam type additives. That plus the E85 should help you pass. Good luck......let us know your results! Link to comment Share on other sites More sharing options...
danbennett2u Posted September 6, 2011 Share Posted September 6, 2011 There is no reason to run 91 octane on a vehicle that is not high compression anyway, just throwing away money. If you are not having detonation issues just run regular grade. I run 85 octane in my legacy in colorado with no pinging (all octane grades are lower at this altitude). I occasionally run a half/half mix of E85 and regular gas just to keep things clean. Be aware though that if you are gunked up in the fuel system you may need to replace the fuel filter after running E-85, as it tends to loosen crud up which then gradually plugs the filter. As far as not passing at Idle... I would say replacing with plain copper NGK plugs is well worth the effort and money. Way cheaper than having to retest multiple times I imagine. Actually unless you are buying walmart plugs NGK coppers ARE the cheap ones ($2 per or less) Link to comment Share on other sites More sharing options...
Rooster2 Posted September 6, 2011 Share Posted September 6, 2011 There is no reason to run 91 octane on a vehicle that is not high compression anyway, just throwing away money. If you are not having detonation issues just run regular grade. I run 85 octane in my legacy in colorado with no pinging (all octane grades are lower at this altitude). I occasionally run a half/half mix of E85 and regular gas just to keep things clean. Be aware though that if you are gunked up in the fuel system you may need to replace the fuel filter after running E-85, as it tends to loosen crud up which then gradually plugs the filter. As far as not passing at Idle... I would say replacing with plain copper NGK plugs is well worth the effort and money. Way cheaper than having to retest multiple times I imagine. Actually unless you are buying walmart plugs NGK coppers ARE the cheap ones ($2 per or less) I agree that running 91 octane is unnecessary. 87 octane runs well in my two Subies. The higher octane of 91 isn't giving you enhanced performance, or lower emissions. Just costing more. I would use E-85 on a regular basis. Your car wasn't designed for it. Yes, the alcohol does a good job of cleaning the fuel system, but is known to degrade rubber parts of a fuel system. So, don't advise running E-85 often. I use the Bosch Platinum spark plugs. The cheapest ones with just one anode. They work fine, plus don't need gapping. Cost maybe$2.00 - $3.00 each. Link to comment Share on other sites More sharing options...
rverdoold Posted September 6, 2011 Share Posted September 6, 2011 Is the measurement performed on a warm or cold engine/CAT? Unburned fuel comes from continious correction from the O2 sensor after the first cat. If the car is warm (actually it shows with 2500 rpm run) that the emmissions are fine. I think the idle rpm is low. Changing sparkplugs to NGK or bosch might indeed help. Cheaper plugs (I consider NGK as not expensive) may have poor insulation 'leaking' spark energy hence poor fuel burn follows to low idle (although the computer should correct for this) Link to comment Share on other sites More sharing options...
280+k 90 Legacy Posted October 16, 2011 Author Share Posted October 16, 2011 Thanks for the help everyone. I tried E85 fuel and it took 100 PPM off the HC. This was still not good enough to pass. Today I took the car to an exhaust place. It turned out the front cat was fine and original. The back cat had been replaced and had nothing left but a ball of wire mesh. Replaced the back cat for $200 and the car passed smog with flying colors. I'll post the final number shortly. Thanks again for all the suggestions. Maybe this thread will be useful to someone else. Link to comment Share on other sites More sharing options...
280+k 90 Legacy Posted October 16, 2011 Author Share Posted October 16, 2011 Passed!!!!Passed!!!!Passed!!!!Passed!!!!Passed!!!! Ok here on the numbers: RPM: 691 %CO2: 13.8 %O2: 1.7 HC (PPM) Max: 120 AVE: 29 Meas: 35 CO (%) MAX: 1.00 AVE: 0.10 Meas: 0.00 RPM: 2662 %CO2: 14.6 %O2: 0.5 HC (PPM) MAX: 140 AVE: 20 Meas: 22 CO(%) MAX: 1.00 AVE: 0.10 Meas: 0.00 Passed!!!!Passed!!!!Passed!!!!Passed!!!!Passed!!!! Hopefully I'll get another 300k out of the car Link to comment Share on other sites More sharing options...
johnceggleston Posted October 16, 2011 Share Posted October 16, 2011 it sounds like the original cat is still good and passes the test, but the aftermarket cat is not good and did not pass. note to self, do not replace original cats, replacements are not as good. glad you got it on the road. enjoy. Link to comment Share on other sites More sharing options...
poolskaterpt Posted October 21, 2011 Share Posted October 21, 2011 For future smog strugglers whose exhaust system is intact (unlike above scenario): -Bosch 2+ plugs - Make sure to adjust to proper idle tach. -stop by the local small airport and run a 50/50 aviation fuel and E85 mix - Run it down the highway at higher RPM than usual 4500 or so to get the CATs nice and warmed up. - Disconnect PCVs and close manifold ports to prevent stalling. - Pull one of the air filters (preferably the one closest to manifold) on a 2.2L This will help your engine burn the fuel more completely and decrease the HC level (hydrocarbon) which indicates unburned fuel, or heavy crankcase gases being vented into the intake. WORKS 60% of the time, EVERY TIME!!! Link to comment Share on other sites More sharing options...
bheinen74 Posted October 21, 2011 Share Posted October 21, 2011 I always wonder if this is why my CA BRAT arrived to me with a ball bearing lodged, should say pressed to not remove, in one of my vacuum lines... it had passed smog right before it was sold to me..... ran like crap too. craptachi.. Link to comment Share on other sites More sharing options...
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