uss_essess Posted May 14, 2009 Share Posted May 14, 2009 (edited) It's a 1989 SPFI GL, no codes. Passed easily at 2500 RPM, but failed at Idle. Here be the numbers: Idle (926rpm): Hydrocarbons (PPM) Limit - 750 Actual - 965 - FAIL! CO (%) Limit - 1.00 Actual - 1.05 - FAIL! CO2% - 12.8 O2% - 0.48 2500 RPM (2465rpml): Hydrocarbons (PPM) Limit - 750 Actual - 160 CO (%) Limit - 1.00 Actual - 0.26 CO2% - 12.6 O2% - 9.61 Now to the question portion. Why am I so far over at idle, and what can I do to fix it? Any thoughts would be great. Thanks in advance for any help. Edited May 15, 2009 by uss_essess Link to comment Share on other sites More sharing options...
Durania Posted May 15, 2009 Share Posted May 15, 2009 When was the last time plugs/wires were changed? Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 15, 2009 Share Posted May 15, 2009 Your idle speed is too high - you may have vacuum leaks. Change the plugs and wires as sugested. Adjust the idle air control valve to get the idle back where it should be. Change the oil and the air filter while you are at it and make sure the PCV is working and all the lines are clear. You really aren't all that far from passing - just a few maintenance items may get it under control. If that doesn't work buy a cheap 3-way catalytic coverter off ebay and add it to the mid-pipe section of the exhaust. That will get it under control for sure and is definately the cheapest way to go if you can do a little rudimentary welding and fitting. Less than $50 for a sure-fire fix is worth it when you consider that it may take hundreds of $$ and many man-hours to make it pass by only fixing the stock equipment. Not that it can't be done, but if it otherwise runs fine, how much time and money do you want to throw at a sub-$1000 car? GD Link to comment Share on other sites More sharing options...
gwilson87 Posted May 29, 2009 Share Posted May 29, 2009 I am having the same problem with my "new" brat. My readings were... High Speed Test HC-84 CO-.15 Idle Test HC-1203 CO-.2 HC can't be more than 220 and im clearly pretty high over that. I have replaced plugs right before the test. Since the test I have rebuilt the carb (the brat still runs the same though) replaced pcv valve and hose, as well as distributor cap and rotor. I have one more free test and I'm still scared I will fail. Any thoughts ? I just might go buy some alcohol to put in with the gas to just get past the emissions. Also my brat doesn't like to idle at its recommended 700 rpm. It struggles to get under 1200 which its required to be under for the idle test. Any help is appreciated. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 29, 2009 Share Posted May 29, 2009 1200 eh? You have a mess on your hands. First you probably have vacuum leaks, and you clearly have a severe miss at idle (vacuum leak related most likely). You are dumping entire cylinders of gasoline that haven't burnt - thus the enormous amount of HC from the idle test. You have to fix the carb and the vac leaks and get the idle down to around 800 - 1000 or you just aren't going to pass Also your cat has had it - that much fuel dumping into the cat will straight burn it out. Get another y-pipe with a good cat or add one to the mid-pipe. Alcohol will not help you with numbers that high. You can expect at most a 50% reduction from denatured alcohol as you can't run more than 1/2 your tank with the stuff - it will also run like total crap and you won't get the idle down unless you fix the carb/vac leaks you have. Pretty much, with what you are telling me, there is no way around it - you are going to have to make some serious repair efforts if you want that thing to pass. I would do a leak-down test and see what you are working with for compression - you may have a couple low cylinders or one really bad one - in which case it will never pass till it's rebuilt. GD Link to comment Share on other sites More sharing options...
gwilson87 Posted May 30, 2009 Share Posted May 30, 2009 Well then... Not exaclty what I wanted to hear :-\ Tomorrow is my last day to get a free test done (since you get 2 free retests). After getting everything back together today it was running a bit smoother and idling at about 1000 or so. If it still fails then I'm gonna go ahead and either replace every single vacuum line and start on the compression tests.... or just buy a 2.2 engine and begin my swap. Thanks for the info. Link to comment Share on other sites More sharing options...
Rust Posted May 30, 2009 Share Posted May 30, 2009 before going in for the test, put in 93 octaine in and run the car for a good hour before pulling up to the testing station. if at all possible don't shut the engine off while waiting in line. Link to comment Share on other sites More sharing options...
gwilson87 Posted May 30, 2009 Share Posted May 30, 2009 Just got back from the re-test. Idle Test (I got the idle to about 900) HC - 1989ppm!!!!! Thats 1769ppm over the limit.... The benefit of this test was the finally did my safety test so I'm clear in that area. I might "sell" the car to my wife and have her register it under my sisters address in iron county where they don't have emissions Even though I know that there is still a problem that needs to be fixed so I won't be at ease, at least I will have license plates... Link to comment Share on other sites More sharing options...
edrach Posted May 31, 2009 Share Posted May 31, 2009 I am having the same problem with my "new" brat. My readings were...High Speed Test HC-84 CO-.15 Idle Test HC-1203 CO-.2 HC can't be more than 220 and im clearly pretty high over that. I have replaced plugs right before the test. Since the test I have rebuilt the carb (the brat still runs the same though) replaced pcv valve and hose, as well as distributor cap and rotor. I have one more free test and I'm still scared I will fail. Any thoughts ? I just might go buy some alcohol to put in with the gas to just get past the emissions. Also my brat doesn't like to idle at its recommended 700 rpm. It struggles to get under 1200 which its required to be under for the idle test. Any help is appreciated. Have you cleaned changed the air filter. A dirty filter will make it run rich. Also, can you lean out the mixture on the carb. I finally got mine to pass by replacing the Hitachi with a weber. Where are you located; if you're in Seattle I have a solution for you. Link to comment Share on other sites More sharing options...
gwilson87 Posted May 31, 2009 Share Posted May 31, 2009 (edited) I'm in Utah and I think its more than a carburetor problem. I might give it one more try but I think I might just hold out to get a 2.2 in there. For-go the whole carburetor in general. Also the air filter was the first thing I changed when I bought the car. Followed by an axle, ball joint, fuel filters, plugs, distributor cap/rotor, windshield, pcv valve and hose, and somewhat rebuilding (heavy cleaning) of the carburetor. Edited May 31, 2009 by gwilson87 Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 31, 2009 Share Posted May 31, 2009 I'm in Utah and I think its more than a carburetor problem. Agreed - you can't get that high of an HC reading without a severe idle miss. It's either a large vac leak somewhere, poor ignition, or low compression. GD Link to comment Share on other sites More sharing options...
ruparts Posted May 31, 2009 Share Posted May 31, 2009 Hi, last time i took my 88 rx in for inspection i had high readings similar to yours, it failed. I had done all the regular tune up stuff the p[revious year and it had passed fine. but I went ahead and put new wires and plugs. but the real thing that I feel fixed it was the O2 sensor, and I verified the EGR valve was operating. I think the O2 sensor was the real cure for my readings, and this is not the first car done this way. I had another one that all i did was take it to insppect, it failed likewise, o2 sensor was all i did to it , shaped right up and passed. the EGR valve must be operational and the tubes and passages from head and in the intake not clogged up which happens sometimes if an engine has been run with a too cool thermostat for a long time which causes excess carbon buildup, motors need the heat to maintain proper A/F mix. also too cool thermostat can cause the fuel inject to think the engine is not warm enough and runs a little rich to make up for it, just like during warm up period from a cold start. just to add to what has been posted already. LOL Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 31, 2009 Share Posted May 31, 2009 Hi, last time i took my 88 rx in for inspection i had high readings similar to yours, it failed. I had done all the regular tune up stuff the p[revious year and it had passed fine. but I went ahead and put new wires and plugs. but the real thing that I feel fixed it was the O2 sensor That's nice and all, but his car doesn't have an 02 sensor. Unless you are talking about the original poster? In which case he was so close to passing that a little denatured alcohol would bring it right in line easily. GD Link to comment Share on other sites More sharing options...
kmghd56 Posted June 2, 2009 Share Posted June 2, 2009 Fought a problem like this in my shop for two days, replaced the pcv valve that was just replaced (stamped made in USA) with an OEM valve. Barely registed on the next test Link to comment Share on other sites More sharing options...
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