Apparent O2 sensor issue - suggestions?
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Apparent O2 sensor issue - suggestions?
My 2000 suburban has been having P134 and P154 codes daily. Not constantly, but probably every 20-30 minutes. I’ve replaced them in the not too distant past (a couple times) so I don’t think it is really a sensor issue. The other current symptom is extremely smoky exhaust when starting up. I don’t think it is bad when driving but definitely smoky on first start up. Any thoughts?
CF Monarch
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My 2000 suburban has been having P134 and P154 codes daily. Not constantly, but probably every 20-30 minutes. I’ve replaced them in the not too distant past (a couple times) so I don’t think it is really a sensor issue. The other current symptom is extremely smoky exhaust when starting up. I don’t think it is bad when driving but definitely smoky on first start up. Any thoughts?
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Thanks. We have done compression tests recently (this has been going on for a while) with no real issues. We have not done a leak down test. Is that likely to produce other results than a compression test?
CF Monarch
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From: kevinkpk
My suggestion, since (I think it is bank 1) drivers side, pull spark plugs till you find the one(s) that are fouled. Since you didn't post the compression test results, other than "good" I have to assume it is (a) valve seal leaking. With 280K on the engine, probably looking at (with what you've posted, and my assumption) either a valve job, or replace heads.