Hello HT my daily driver (2000 honda civic si, d16y8 NA) has had problems recently, I first noticed a problem comming home from work (in the rain).
when I got off the highway and proceeded a red light. I went to step on the gas and it reached 7k rpm then quickly dropped down to 4k and wont go higher then that, i had a cel with code 45 (running to rich or lean) and sure enough when i got home I floored it and smelt extreamly rich. Today all i have done was changed the fuel filter and maf sensor, i also checked all my fuses and made sure connections were tight. I checked other posts saying it could be fuel pump, injectors, o2 sensor or bad grounds. Another important note, when I cold start I can step on it and reach 7k rpm for around 10 seconds before it bogs out and goes limp again?? Thanks for the help guys, if you need any more info let me know

 

No expert here but also possible vacuum leak, also spark plugs. I just went through a issue of surging and it ended up being my spark plugs. When cold it ran ok but once car warmed up it would big down unless I hit a sweet spot than I would get a surge of power.

 

I just took a look at my plugs and they looked clean still and all dry if im in 3rd cruising and then press my pedal down all the way the car bogs out and sounds like it's mis firing?? Tommorow im gunna check all my voltages at the ecu and determine from there I guess...

 

I'm no expert either, but it might be worth checking the timing belt as well. I just got a used motor and my mechanic checked the cylinders and said one of them was burning rich. He also noticed that the timing was off and part of the timing belt cover had melted. Bad timing can cause loss of power.

 

You didn't bother to check what you found on other sites?

 

thanks, ill check it out

 

Sounds like a bad O2 sensor or both, Either replace them if you still have the code reset the ECU or just unplug the battery to clear the code and see if it revs freely

 

**FIXED** The catback was clogged, didn't see any posts or fix on the internet about that! Just did a temporary fix by drilling holes in the catback hahaha, so redneck but I have a new one ordered. Car never ran better other then being loud and obnoxious