i have a 92 si with a stock motor and after about 5 min of it running the engine will actually idle at 100 rpm then try to stall and go up to around 500. i searched for it and i did some of the sugg and didn't work. i got a new main relay and i re did the engine ground. im thinking its a iacv or a leak in the im any help would be appreciated

 

Check your map sensor I'm having sorta the same problem

 

thanks ill try it

 

on my b18b, i was having the same problem along with a little roughness in the idle also. I took off the IACV and cleaned it with throttle body cleaner and then took the intake off and used the rest of the bottle into the IM. I then seafoamed the motor. After doing this it raised my idle and smoothed it out, i then actually had to adjust the idle down using the idle screw. This at least worked for me!

 

How are you reading 100RPMs? I don't think your stock tach shows that.

 

it shows it almost at the line it would be at if it was shut off so i don't really know also im not throwing any cels

 

I would just raise te idle on it little, if the car is running fine otherwise.

 

I think the lowest line on your tach is 500 rpm. Sounds to me like you've got a vacuum leak and a hunting ECU and idle is coming down to around normal you're just not used to it.

 

with these gas prices you should be happy your motor idles at 100rpm

yay for vtec