Rough Idle

[jabber13]

My 1994 Mx3 V6 automatic is having some issues that I'm hoping I can get some advice on. In reading some other threads I've seen similar issues but nothing exactly like mine.

The engine starts up fine and when cold there are no problems. But, similar to other people's issues, once the engine is warm and the RPM's drop below 1k I start to have a very rough idle. It is not consistent, there is no pattern or predictability to it. It just sort of shudders as though its choking, it never dies, just kinda jolts. When it jolts the RPM's dip a bit.

When I give it gas, there is no problem. The engine is not really sluggish by my estimation, it is only problematic when I'm stopped and the RPM's drop below 1k to about 700 RPM's.

I'm going to replace the fuel filter to start. Any other suggestions or ideas about what might be wrong or what I might do to fix it? Thanks.

JB

[tehbrookzorz]

Have you checked for vacuum leaks in vacuum hoses and/or your air intake tube between the air box and the throttle body?
That's not necessarily the problem but it could help narrow things down. I'm not an auto tranny guy so there are more things at play than I'm fully aware of.

[jabber13]

Right...thanks for the tip...I'll check it out. Any other suggestions out there, keep em coming.

[jabber13]

the vaccum seal at the throttle body is good. what else might be causing the hesitation when i'm idling?

[alreadydefective]

im probably not right, but if your idle adjustment screw isnt right, then it could be messing with your idle, do you know if its ever been adjusted?

[ariesdude]

Could be coolant temperature sensor and/or O2 sensors -
Replace coolant temperature sensor because its easy and cheap - if the problem persists afterwards you can look into changing the O2 Sensors.

[jabber13]

could it be a misfire issue?

[jabber13]

I believe it is a misfire after having a conversation with some people. What can I possibly do to resolve it if it is?