Very Rough Idle

[JDMPrelude23]

I got a 89 accord lxi 5spd. And whenever i turn my headlights on, the car vibrates like crazy!! Its a cellphone vibrating OD! and whenever i press the brake pedal it also vibrates very hard...... What are some things i could do/check to minimize or stop the rough idling????

BTW the rpms go really down, almost to zero when it starts to shake.

[Dr_Snooz]

What is the idle speed when you don't have the brake depressed?

[YK86]

Sounds like it happens when there is a load on the engine. I'd be looking at a couple things:
-broken or worn engine mounts
-idle speed set too low
-IACV not opening enough (clogged or broken) to bump up the idle when there is a load.