CEL Codes Help

[Hovjm23]

So I have a regular 1998 Accord, and I'm getting these two codes:

P0500 -Vehicle Speed Sensor Malfunction
P0420 - Catalyst System Efficiency Below Threshold (Bank 1)

I'm pretty sure that the first one is pretty straightforward. My speedometer just stopped working out of nowhere, so my guess is that I'll have to replace the VSS, like the code is saying. Anyone able to find any online for cheap?

But my main problem here is the P0420 code. My car has been very sluggish lately, especially in first and second gear, in high RPM. It seems to want to "pull" more in the lower range, and it wasn't always like this. I've been hearing that the problem is either my catalytic converter, or my oxygen sensor. What should I do?

Also, during a cold start, my car would start at about 1,800RPM (like normal), but would drop to 200-300RPM a few seconds later! Any input? Is this related to the P0420 code?

Thanks, a lot!

 

[finch13]

P0420 is not a big issue, you simply need a new cat converter. The computer is good at determining if the cat or the O2 sensor is bad. You can feel the exhaust coming out of the muffler, if there isn't as much as their should be the cat is probably clogged, which could cause your sluggishness and low idle. If it isn't clogged, pick up a few HELP! brand 18mm spark plug defoulers at the auto store for less than $10. Drill one of them out with a 1/2" drill bit and put it on the O2 sensor, then thread the second defouler onto the first one and thread it back into the cat. Pull the #30 ECU fuse and allow the codes to be reset and plug it back in. The CEL should go out and not come back, sometimes it does. You will not pass tailpipe emissions if FL has it, but you should pass OBDII check or whatever they test.

As far as the VSS goes, try unplugging it and cleaning out the connectors with brake cleaner. Sometimes they get dirty and will cause the speedo to act strange, but if it's totally dead you may need a new VSS.

 

[Hovjm23]

Thanks for your response!

I'm happy FL has no inspections, whatsoever. No tailpipe or OBD checks.

But how would I know whether or not the cat is clogged? And if it is, do you recommend gutting it, getting a new OEM one, or getting a high flow cat?

 

[Drift]

If there is a VSS code, that is what causing your sluggishness. The p0420 is just saying that the sign wave produced by the primary o2 sensor is is roughly the same as the sign wave produced by the secondary o2 sensor. (In other words, your cat isnt working any more).

Fix the VSS first. And then just put a non-fouler in the cat to get rid of the p0420.

 

[Hovjm23]

Excuse my ignorance, but how can a VSS code cause sluggishness?

 

[finch13]

The ECU relies on input from the VSS and a lot of other sensors to determine spark timing, injector pulse width and frequency, valve timing, etc. to provide the most power. The system is only as strong as it's weakest link, so one small problem can cause some weird driveability issues.

 

[Drift]

The ECU relies on input from the VSS and a lot of other sensors to determine spark timing, injector pulse width and frequency, valve timing, etc. to provide the most power. The system is only as strong as it's weakest link, so one small problem can cause some weird driveability issues.

:werd:

If any of the ecu's inputs fail, the ecu freaks out and goes into a safe mode where is it will run a really conservative fuel and timing maps. The ecu also has something called "per-gear fueling," where is uses the VSS and RPMs to see what gear the car is in to adjust for the increased load that is caused by being over-driven. (along with the MAP sensor of course)


And lastly. . . Its Essential for the most important part of honda's. . . .













VVVVTTTTTTEEEEEEEEEECCCCCCCCCCCCCCCC!!!!!!!!!!!!111!!!!111one!11

 

[finch13]

Well put.

 

[Hovjm23]

I will be getting to work this weekend. But what do you guys recommend for a $500 "everything" budget. Gutting the cat, high flow cat, or OEM?

I want to do this the best way possible, under budget, with little "rice" exhaust noise. Thanks again for all input!

 

[Drift]

How about no cat?