Buck Savage
New Member
I have a 1995 California Honda Civic DX with 1.5L 4 Cyl D15B7 (223,000 miles). It failed test 1, with only hydrocarbons too high. [118 ppm instead of 68ppm at 1702 rpm/15mph and 61ppm instead of 44ppm at 1914 rpm/25mph]. Engine timing was 15 degrees.
I checked my records and noticed that oxygen sensor had not been replaced (at least since before I got the Civic at 107k miles). The old sensor was a Denso 234-2311. The new one is 234-4009. The Denso website says that is the right one. 234-2311 doesn't show up anywhere, except for a badly-spelled Asian website.
At 179k miles, the car got a new timing belt, water pump, tensioner, spark plugs, wires, rotor, cap.
I also:
1) replaced air filter (old filter was pretty clean).
2) looked at spark plugs-- 2 of them were slightly loose. One had a screw-on nubbin (that the wire slipped onto) that wouldn't tighten, like it was stripped. I found another nubbin in the spark plug locker that screwed on tightly.
3) remove AC compressor, radiator and fan, wiring harness, piping across the front of the car (it interfered with getting a wrench on the O2 sensor). Some piping and the internal radiator are still in place. The AC system was empty of refrigerant when I got the car.
4) checked and adjusted valve rocker arm clearances slightly
5) change oil and filter
6) check compression: cylinder 1:135, 2:135, 3:143, 4:146 (it spiked higher)
7) check PCV valve (works)
Twice after replacing the oxygen sensor, the check engine light came on temporarily. I tried to get a code (put clip across the connector), but got nothing.
Hoping for a little improvement, I had the car smogged again. Bad news. Now I was a gross polluter. Engine timing was only 8 degrees. At 25mph, HC was up to 283ppm, and all the numbers were worse. For example CO rose from 0.12 to 4.15 (see both test results in attachments)
.
I went home and checked the timing with a timing light, and it was 15 or 16 degrees. I have holes in the muffler and midpipe, which I taped up before getting the smog checks. I have ordered new ones, which I will get soon. Also, I just went on a 900-mile road trip and got 44.2 mpg (after all of what I reported here).
I checked my records and noticed that oxygen sensor had not been replaced (at least since before I got the Civic at 107k miles). The old sensor was a Denso 234-2311. The new one is 234-4009. The Denso website says that is the right one. 234-2311 doesn't show up anywhere, except for a badly-spelled Asian website.
At 179k miles, the car got a new timing belt, water pump, tensioner, spark plugs, wires, rotor, cap.
I also:
1) replaced air filter (old filter was pretty clean).
2) looked at spark plugs-- 2 of them were slightly loose. One had a screw-on nubbin (that the wire slipped onto) that wouldn't tighten, like it was stripped. I found another nubbin in the spark plug locker that screwed on tightly.
3) remove AC compressor, radiator and fan, wiring harness, piping across the front of the car (it interfered with getting a wrench on the O2 sensor). Some piping and the internal radiator are still in place. The AC system was empty of refrigerant when I got the car.
4) checked and adjusted valve rocker arm clearances slightly
5) change oil and filter
6) check compression: cylinder 1:135, 2:135, 3:143, 4:146 (it spiked higher)
7) check PCV valve (works)
Twice after replacing the oxygen sensor, the check engine light came on temporarily. I tried to get a code (put clip across the connector), but got nothing.
Hoping for a little improvement, I had the car smogged again. Bad news. Now I was a gross polluter. Engine timing was only 8 degrees. At 25mph, HC was up to 283ppm, and all the numbers were worse. For example CO rose from 0.12 to 4.15 (see both test results in attachments)
.I went home and checked the timing with a timing light, and it was 15 or 16 degrees. I have holes in the muffler and midpipe, which I taped up before getting the smog checks. I have ordered new ones, which I will get soon. Also, I just went on a 900-mile road trip and got 44.2 mpg (after all of what I reported here).
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