Thank you all for your suggestions yesterday. I got an OBD II ode reader and here is what I found

01/03: P1298: the OBD device says DTC definitions not found, but Google says this is "Electrical Load Detector" and I found some youtube videos on how to replace it, seems very simple.

02/03: P0135: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)

03/03: P0141: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)



I do not know which is the order in which the error codes occurred, I would assume 1 is the oldest and 2 and 3 are the newer codes

I reset all codes, Check engine light is now OFF (that's good) but the now I have the 01/01: P1298 (first code). I started the car for about 1 minute and codes 2 and 3 didn't come back, I assume they would appear again if I try to actually drive and engine warms up.

Nothing about the Vehicle Speed Sensor so far.

I plan to troubleshoot the O2 sensor to make sure no cable is loose/corroded and if cable looks good, buy a new sensor.

any other tips appreciated.

Thanks

O² sensor is a frequent culprit.

but what doesn't make sense is why the speedometer jumped all over the place. That would indicate a VSS or some other electric trouble. Anyway, I will try an O₂ sensor first

O2 sensor may cause a stumble and maybe a misfire, but it is unlikely that it would be the reason for an electrical glitch making the speedo jump around. I am not familiar with a "sensor heater."

I think something in the throttle module could be at fault.

---

High on a threshold yearning to sing
Down with the dancers having one last fling

Take a look at this thread and this Honda service bulletin, it sounds like what you might be seeing. Common cause seems to be a blown fuse and damaged insulation on a wiring harness.

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[honda-tech.com]

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GGD
Take a look at this thread and this Honda service bulletin, it sounds like what you might be seeing. Common cause seems to be a blown fuse and damaged insulation on a wiring harness.

[www.tegger.com]
[honda-tech.com]

That sounds a lot like my problem, even the lights on the dashboard seemed to be dim now that I think about it. It was during lunch time, I drive with lights ON so the effect of the dash lights flickering was not that apparent but I did notice it.

Thanks a lot, won't have time to deal with this right now, and weekend's forecast predicts for more snow so it may be a while until I can put the car on a lift and deal with that cable. But I will check the fuze ASAP.

If the fuse is blown, that's probably a big clue that it's this problem, and replacing it will probably fix things until the harness rubs in just the right way to short something. Maybe carry some extra fuses until conditions are right to inspect / repair the wiring harness.

I has P1298 on my Civic (2002), and it seemed to cause over voltages that blew headlights quite frequently. Since replacing the part, the headlights never blow. This may be the root of your problems.

I'm not so sure that you don't also have a VSS problem. IIRC, VSS problems don't always throw a code.

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macphanatic
I'm not so sure that you don't also have a VSS problem. IIRC, VSS problems don't always throw a code.

good point. since the failure occurred at the same time, I am thinking that maybe it is not the sensor itself, but perhaps the wire is routed through the same harness as the O2 wires. will post an update in several weeks when I figure it out.

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space-time

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macphanatic
I'm not so sure that you don't also have a VSS problem. IIRC, VSS problems don't always throw a code.

good point. since the failure occurred at the same time, I am thinking that maybe it is not the sensor itself, but perhaps the wire is routed through the same harness as the O2 wires. will post an update in several weeks when I figure it out.

If I'm reading the tech bulletin correctly, there are three possible codes that one might see along with the blown fuse, "electrical load detector", "primary heated oxygen sensor", or "vehicle speed sensor", so I suspect that either the wiring for all three go through that harness, or they're all protected by the same fuse. Since you got two of the three, and experienced behavior that would have pointed to the third one, there's a lot of evidence pointing to the damaged insulation.

But if the fuse is actually blown, and there is visual evidence of the harness rubbing on the intake manifold bracket, that would really nail things. Otherwise, suspect the sensors.