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Discussion Starter · #1 ·
Tags are up for renewal this year (this month actually). CEL has been coming on sporatically for a while now and I've talked myself into believing its bad O2s. I thought I'd try to sneak through DEQ and not have to worry about it for a while. No such luck - stinking environmentalists and their DEQ! THC levels were too high. 3.something g/mi and they need to be at 1.2 I finally ran a check on the CEL codes and sure enough the F & R O2 sensors were bad. $62.99ea and a little under an hour under the car later, the 02s were swapped (took so long because Haynes said 1 O2 was in front and 1 was behind the Cat. I changed the rear, but thought I had changed the front. A thorough hand-inspection behind the cat turned up empty and I moved toward the front of the car, where I found the other sensor. Damned Haynes!). Cleared the CEL register by disconnecting the ground from the battery and waiting 20 minutes before depressing the brake pedal (to ground the loop). I went to DEQ again and failed. THC had dropped to 1.3something and was still over the 1.2 g/mi limit. I am naively attributing this to the fact that the O2s had been out of commission for over 10,000 miles (guessing) and had tripped the computer into its richened A/F ration for that entire duration. Probably a lot of build-up in the cat. I am about 60 miles into a bottle of injector cleaner to which I added a fresh tank of 92octane gas. The only other trick up my sleeve is to run the piss out of my car for a few hundred miles to try and burn up any residual filth in the cat. Per a strong sentiment on Probetalk, I will be switching from Castrol Syntec 10W30 to Mobile 1 synthetic 5W20 at my next oil change. Any other suggestions? Any tips on passing DEQ (just give it time?) that will also help my car?

BTW, no more CEL. That's good at least...



[Edited by BOWDWN2MX6 on 05-02-2001 at 12:03 AM]
 

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Go grab a bottle of Sure Pass or other related stuff. It should drop your levels just enough to pass. Be happy I actually passed the sniffer test when i went to smag and the damn garage mechanic decided to fail me for my EGR hoses not saying they are made specifically for EGR use. He was obviously just trying to have me run again for more money, so I went to another shop who just ran it and only cared if I actually passed the sniffer test. Funniest thing is the first mechanic didn't even notice the completely non-CARB certified headers on the engine. At least if he had failed me on those it would have been valid.:)
 

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Discussion Starter · #3 ·
Oregon DEQ must be very different from yours. pre '75 - no DEQ requirements. '75 - '96 (w/ OBD) they first set your car over what I am guessing to be a vacuum beneath a grate in the floor, which is supposed to reveal any exhaust leaks to an ultraviolet light. Fail here and you don't pass. Next, they move your car onto a dyno, where they test for THC CO2 and one other emission (can't remember right now) while driving the car through various RPM ranges on the dyno rollers. They control this test via remote control while sitting behind the wheel in your vehicle. All the while, you're forced to wait in a small waiting room with a window while some asshole government worker with no regard for your vehicle and no mechanical training whatsoever runs these tests. '96 and newer vehicles have OBDII diagnostic plugs which mesh with diagnostic systems at DEQ and they run the tests this way. It sucks.
 
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