So I got a 2000 honda civic ex. Brand new to Hondas. The car doesn't go above 20mph even stepping all the way on the pedal and it revs up and down by itself in park. When I let off the pedal it makes a small thrust to push more. I've changed the solinoid and added a new cold air intake. Still don't work, what could this possibly be or any ideas? Thanks in advance!

 

What codes is it throwing?

 

it shows p0135 and p0141 I'm still not sure

 

Those are o2 sensor codes. Check the wiring, and replace them if necessary. It will not run properly at all with P0135.