I have in my integra a n/a b20vtec build. B20z block and gsr head with b16 cams 11.2.1 compression valve train all that. I have a victor x edelbrock mani with blox 70mm tb and new fuel filter/fuel rail/injectors. The issue I'm having is on going but 1 out of 5 times I drive there is no issue but mostly it is ongoing. The issue is that when I sit at idle my car*idles at 900 but will consistently drop to 100 and jump back up to 900. The lights dim when this happens and it happens at red lights and whenever idling. Sometimes it does it sometimes it doesn't. Also while driving it will do the same thing only it will go from 3000 rpm to 100 then shoot back up. Like it chokes for a second then releases back. It jerks the car back for split second. I have cleaned iacv and bled my coolant for air bubbles. I ordered walboro 255 fuel pump today as well. I don't think my intake mani has an fitv. Any ideas guys? Please help!

 

Someone help me out please!

 

throttle body has fitv not intake manifold
just because you cleaned IACV doesn't mean its fixed. sometimes they just stop working right
you might have a vacuum leak have you checked fro that?

what about brake booster is it working properly?

and also the engine will not run below 400rpm first mark is 500 rpm
built engine will barely run at 500 rpm

have you adjusted your idle according to manual or just eyeball it?
check your timing.
check your spark plugs and measure wire resistance
check your coil make sure its within specs.
check your fuel filter

I had similar symptoms from dying ignition coil

 

No vaccum leaks and brand new fuel filter. I know the iacv works properly. I checked it and when cleaning it I took a power and ground cable to it and opened it ip to clean the inside real well. Now that I think about it I think the coil could be the issue. The ignition system is all stock right now. I'm gonna order the msd kit with wires plugs blaster coil and distripbutor cap and rotor and see if problem fixes. Thanks a lot

 

you don't need any of that **** unless you running 300whp build
stock components are sufficient enough
if you have hondata and want to blow your cash on something get the coil on system for it.

 

I will look into that asap