Idle wander

General Fiero Maintenance including oil changes, air filters, suspension refreshes, restorations, painting, etc.

Moderators: The Dark Side of Will, Series8217

Post Reply
wolken
Posts: 25
Joined: Mon Mar 27, 2006 2:56 pm

Idle wander

Post by wolken »

I have a 2.5L 1984 4 speed Fiero. When you start the car cold it high idles at about 2500 rpm until it warms up and when it does warm up it idle wanders between 700 - 1200 it will sit on 1000 but then will drop and recover. My question is if somebody has a suggestion on what might cause this and if that high idle is a little too high (it seems like it to me).

Thanks

\/\/olken
"Hey look a Fiero for 400 bucks...."
I had no idea what i was getting into...

-Me August 04.
Mach10
Mach10 offers you his protection.
Posts: 2481
Joined: Thu Jul 14, 2005 6:50 pm

Post by Mach10 »

My 4cyl ALWAYS idled high... But mine did at 2500 too until I found the problem.



It's that STUPID hot air intake valve.

When cold, the valve is open, which makes it into a nice big vacuum leak.

which promptly disappears when the thing gets up to temp.

But in any case, the 2.5L ALWAYS idles high when cold... 1500rpm is pretty normal, IMHO.

Look for that fucking stupid flapper valve on the side of the air intake with the vacuum line running to it. Take off the line and plug the vacuum port at the TBI.
"Oh, this is too good. She thinks you're a servant... Cause you're black! This is greatest moment in my miserable life... Sooo-ey! I LOVE RACISM!"
wolken
Posts: 25
Joined: Mon Mar 27, 2006 2:56 pm

thanks

Post by wolken »

I will check that out, now to figure out the stumbling idle.
"Hey look a Fiero for 400 bucks...."
I had no idea what i was getting into...

-Me August 04.
Post Reply