check engine light

I started my car one morning to go to work and after my car had warmed up, the check engine light and ATTS light turned on and my rpms started to jump up and down. I don't know much about cars, any info would help. Thanks. I just checked the codes P0505 P0401

I have a '99 Base.. I have a few issues. I am hoping they aren't issues at all. I just got the rear main changed, clutch replaced, and the serpentine done.. In the past week, I went to vtec and then had a flashing CEL... but it went off after 10 seconds, took my OBDII and no codes were found...

Okay, so I have a '91 Si 2.1 4ws. It's time to renew my registration, but first I need to pass emissions testing. On a car of this age, they just give you the old tailpipe test and check the gas cap. I have no trouble passing those, as my emissions are fine. The problem is, a car will fail...

I have a 2000 prelude with an automatic to manual swap and i have a check engine light on because it still has the original ECU. I was wondering if it would be easier/cheaper to go and buy an ecu for a manual, or if it would be possible to take it to a tuner and get it fixed.

Hey guys i was driving today and next thing i know my check engine light comes on. I pull over and i see code 43 and code 1 i believe. Code 43 it has been an on going thing and the car runs fine im just not sure what can be making the light come on. Than Code 1 i am confused about do you guys...

The other night my check engine came on again. I had the code read and found out it was a P0420 or "Catalyst System Efficiency Below Threshold (Bank 1)". I was wondering if anyone has an idea of what might be wrong. The car is running perfectly. The only thing I did to it recently was put some...

okay so insted of paying over $100.00 for a cold air intake, i made my own for about 20 bucks. I used dryer hosing and hose claps, but i didn't make a way for the vacuum hose coming from the valve cover to fit in, because i was told it was not a necessity, that i would just need to put a filter...

Hey I put on a new exhaust not too long ago from headers all the way back. Both oxygen sensors are connected but the check engine light code reads a problem with the sensors-this only happened when I changed my exhaust, can anyone help me figure out how to get the light off?