5-wire o2 sensor: email correspondence with Global Automotive

[Danronian]

Oh, i didn't think about how it is a pain to get the old sensor off. It would make sense if he cut off the old plug to fit a socket onto the old sensor, but it wouldn't make sense to cut the new plug off of the sensor since it could be tightened with an open-ended wrench enough to make it tight.

[DRW]

They make special tools just for O2 sensors. Here's a page of them. I have #12100.
http://www.sjdiscounttools.com/vehic...sor-tools.html

[1993CivicVX]

Originally Posted by DRW

They make special tools just for O2 sensors. Here's a page of them. I have #12100.
http://www.sjdiscounttools.com/vehic...sor-tools.html

I was going to remove it myself but the tool was $40 and I figured it'd be cheaper to have the mechanic remove the old one and install the new one. He charged me $15 to do it. I watched him do it and he didn't have the tool and before I could say anything *snip* he cut the wires so he could unscrew the part. I don't think it's the wrong part. I mean, it looks the same as the old one and it fits into the pace where it goes into just fine. But I would like to get to da bottom of it.

[DRW]

Let me back up a bit. If I ignore all the stuff about the O2 sensor, and just read where you have engine power problems and sputtering issues, then my first thought would be to replace the sparkplugs, plug wires, distributor cap and rotor. That is, if they haven't been replaced in the past two years. Those items have a reasonable cost and are simple to change. I consider them to be normal wear items and replace them at the first sign that my car isn't running at it's best.

If any of those items are causing a misfire, the symptoms would be sputtering and power loss under certain conditions. Those conditions vary from car to car, but overall the sputtering usually doesn't happen all the time.

A major characteristic of a misfire is that the gas in the cylinder doesn't ignite. So when the exhaust valve opens, raw gas goes down the exhaust, and along with it goes the oxygen that didn't burn with the gas. Since you have an oxygen sensor in the exhaust, it reads large ammounts of oxygen, the ecu thinks the mixture is too lean and reacts by adding more fuel. It's similar to a bad O2 sensor, they both make the ecu add more fuel. If the ecu has enough capacity, it can add enough fuel to make the misfires worse, which might lead the ecu to think the O2 sensor is bad. It's possible the logic in the ecu is setup to flag a bad O2 sensor under these conditions. OTOH if your car has electronic ignition (distributorless) then the ecu has a chance to diagnose the difference between a bad O2 and bad ignition circuit.
HTH

[1993CivicVX]

Originally Posted by DRW

Let me back up a bit. If I ignore all the stuff about the O2 sensor, and just read where you have engine power problems and sputtering issues, then my first thought would be to replace the sparkplugs, plug wires, distributor cap and rotor. That is, if they haven't been replaced in the past two years. Those items have a reasonable cost and are simple to change. I consider them to be normal wear items and replace them at the first sign that my car isn't running at it's best.

If any of those items are causing a misfire, the symptoms would be sputtering and power loss under certain conditions. Those conditions vary from car to car, but overall the sputtering usually doesn't happen all the time.

A major characteristic of a misfire is that the gas in the cylinder doesn't ignite. So when the exhaust valve opens, raw gas goes down the exhaust, and along with it goes the oxygen that didn't burn with the gas. Since you have an oxygen sensor in the exhaust, it reads large ammounts of oxygen, the ecu thinks the mixture is too lean and reacts by adding more fuel. It's similar to a bad O2 sensor, they both make the ecu add more fuel. If the ecu has enough capacity, it can add enough fuel to make the misfires worse, which might lead the ecu to think the O2 sensor is bad. It's possible the logic in the ecu is setup to flag a bad O2 sensor under these conditions. OTOH if your car has electronic ignition (distributorless) then the ecu has a chance to diagnose the difference between a bad O2 and bad ignition circuit.
HTH

Hey, thanks for that. My car has a distributor. The swapping out of the o2 sensor was a last resort--I had replaced/checked all the other possible culprits. My o2 sensor was most likely bad since when I replaced it the problem of sputtering was fixed. Of course, then there was the new problem of a CEL. Thanks for weighing in with that clarifying explanation.

[Nden]

odd, i just sent back my L1H1 to them a week ago. vague response only 1 email so far. Only code thrown was for the o2. Looks like i'll have to get my Pre-Paid Legal lawfirm involved & send them a "nasty-gram" in order to get a replacement/refund. sigh.