I've posed this question before but I don't remember what the conclusion was.

My 93 accord (auto) shakes like hell at idle when in gear (not Park or Neutral). It shakes so good that a 2 bit whore would have a good time in my car.
I've been in several others that do this as well.

For years I've just dealt with it, but since my crank bolt has come loose twice and now my oil pressure switch is loose, I've decided to try and fix this.

I think someone mentioned a crack in an air line, to which I have found none. Does anyone know what causes this violent shake?

6/8/2007 11:43:43 PM

motor mounts? My dad's 91 auto Accord has a similar shake at idle in gear (though yours sounds a lot worse). Though on his it hasn't really caused any serious issues, it's just annoying.

6/9/2007 12:02:02 PM

I need to replace those as well, but I've seen on several forums that replacing them usually isn't what's causing the engine shake.

Just replaced oil pressure switch today...that sucker was leaking not loose.

6/9/2007 2:03:59 PM

so i take it that you've checked the engine mounts and all that (the vacuum operated one). your front engine mount is probably broken (inconsequential, but important nonetheless).

also have you cleaned out your idle air controller?

it's located on the rear of the throttle body attached to two small coolant hoses.

it's got a fine mesh that gets clogged with dirt pretty easily. make sure you get it all out and when reattaching, replace the figure-8 o-ring.

i did that to my accord and it purrs. takes 30 mins to clean and reattach. i didn't unhook it from the hoses (b/c you'll have to bleed the coolant system), but i did scrape the carbon off the mesh, used compressed air to get all of the dust out, (you might not want to do the next thing) using a rag held under the controller, spray through the mesh using throttle body cleaner spray until the stuff runs clear.

i let it dry for a while and then started the car up. it worked like a charm.

might be different for you.

[Edited on June 10, 2007 at 12:31 AM. Reason : it's a $200+ part if you replace it.]

6/10/2007 12:28:16 AM

I definately need new mounts, but need to get the source of the problem before I end up killing a set of mounts. That rear one (vacuum operated one) looks to be a PITA to work on.

Thanks for the info on the idle air control valve, didn't know that was a part to be cleaned.

6/10/2007 10:27:08 AM

typically, they don't want you to touch it, since there is a large chance that you can render it inoperable (if you try it with the car running - which is stupid), but at the time i didn't give a damn and did it anyway since it seemed like common sense.

the figure-8 oring is like $5 at the dealer though, at least it was for me.

it's a PITA to get to and unscrew. take your time and cursing helps.

it doesn't help to do it in the middle of the day, sweating your balls off.

[Edited on June 10, 2007 at 11:34 AM. Reason : eh]

6/10/2007 11:34:11 AM