my engine will not stop revving.....

If I'm not in gear the engine will just keep revving, not even the same rpm's... sometimes when it's cold it'll rev 2700 - 3000... other times it'll do 2500 - 2700.

it has been doing this since I've bought the car... I replaced a broken oxygen sensor (the owner said that's all I needed)

I cant figure it out...

it's a 93 Civic Ex coupemanual (I think) with 200k

please let me know this has happened to you or someone you know...

 

update.... I have reason to believe that it may be my IACV (I tried to adjust my idle speed, so what you do is while the engine is running you take out the plug in the IACV and adjust the screw to lower/raise the idle speed than reinsert the plug and reset the error code by removing the 7.5 backup fuse.

Well I tried to do this but when I removed the plug the idle just dropped to around 600rpm without revving and the car just started shaking really hard... after awhile I plugged the plug back in and it went back to revving like before.... any thoughts or suggestions?

 

does the engine speed pulse up and down?

 

I'm not sure what you mean by "pulse".. but it will be going from 2300k to 2700k then back to 2300k in a matter of one second.

 

I was thinking I should just drive around without the IACV plugged in, so I could save the gas being burned when it revs... is that a bad idea?

 

it might make it worse. i would check into replacing it. IACV- Idle Air Control Valve. its messing up your idle.

 

I'll probally end up replacing it.... but today I was checking the pcv hose... (haynes manual say to pinch with some pliers and it should make a clicking noise or something while the engine is running otherwise the pcv should be replaced..) and there was no clicking noise so I guess I have to replace that aswell..... anybody around the CT/Hartford area that can help me out with all this ****.... I need a OBD 1 scanner as well.... I don't want to have to pay the 100 bucks to get it done at a service shop but i don't want to pay the 400 to get my own.... shiiit....

Suggestions/Comments are much obliged.

 

P.S. I drove to the mall and back without the IACV plugged in and all I had to really worry about is keeping the idle high enough so it didn't die.... I think my tach is off.... it says its idling at like 1200k when it dies.... and the whole car starts shaking at that idle speed.... how do i adjust my tach?