As stated in the title, both VSA and Check Emission lights went off.

My car had a weird problem last night where the RPM's would randomly fluctuate by about 200 while my foot was still. Now here it is the next day and the lights went off while I was driving home. The car would suddenly drop in RPM's and feel as if it had lost power as before and the VSA would activate and trigger the ABS on small, normally harmless bumps in the road. Any clue what this could be?

I did a quick check under the hood and everything looked alright from my eyes. I did not check fluid levels however. I have 90,000 miles and the only thing that may not be up to date is the spark plugs (never been changed). The only engine mods I have are a comptech icebox and header.

I haven't ran the codes yet but I plan on getting it looked at tomorrow if possible. Thanks in advance!

 

Most autoparts stores will do a free scan on the PCM for error codes. The codes start with the letter P and have four numbers, like P1234.

 

This happened to me last weekend. I was going to diagnose it myself, but while I was trying to get my HDS working, the battery died. After a jump, the lights were off, and no codes stored.
Did you ever get to the bottom of this?

 

you have an HDS? was that expensive?

 

Lightus, i've had my car do something like that and it turned out to be the airflow sensor in the intake.

 

Yeah it turned out that the accelerator position sensor went bad some how. Got replaced and haven't had any problems since.

 

I got a knockoff on Ebay a while ago, but didn't have any reason to use it until a couple weeks ago. Of course when I needed it, I couldn't get it to work. Being an engineer, I tried to troubleshoot it, but I got so caught up in solving the problem I forgot I left the key in the ON position without turning off the climate control, and the battery died.

I'll keep an eye on the accelerator position switch and the intake airflow sensor.
thanks!