Topic: 3000 RPM idle!!! Need help.

[TheNewbie]

I spent the day Sunday changing my water pump out (in the snow ). I got it all back together and it's running at 3000 RPM now!!!

All of the vac lines look like they are plugged in.  And I took the IAC out and gave it a good cleaning.  I had someone switch the ignition on while the IAC was out of the throttle body and still plugged in and it did move when he switched it on, so I'm pretty sure that it's in good shape.

And the throttle plate is sitting perfectly flat.

What else could cause this? This is my daily driver and it's undriveable right now.


It's a 95 YJ 2.5.

[sharpxmen]

I spent the day Sunday changing my water pump out (in the snow ). I got it all back together and it's running at 3000 RPM now!!!

All of the vac lines look like they are plugged in.  And I took the IAC out and gave it a good cleaning.  I had someone switch the ignition on while the IAC was out of the throttle body and still plugged in and it did move when he switched it on, so I'm pretty sure that it's in good shape.

And the throttle plate is sitting perfectly flat.

What else could cause this? This is my daily driver and it's undriveable right now.


It's a 95 YJ 2.5.

vac leak or IAC is the only thing that can cause this. For 3000 rpm i am thinking can only be the brake drum vac line or the line that goes from the valve cover to the intake (below where the throttle body is mounted), or the IAC.

Can't be anything else as without air won't idle that high.

[TheNewbie]

vac leak or IAC is the only thing that can cause this. For 3000 rpm i am thinking can only be the brake drum vac line or the line that goes from the valve cover to the intake (below where the throttle body is mounted), or the IAC.

Can't be anything else as without air won't idle that high.

That's what I thought too.  I'll just replace those vac lines after work today.  They all seem to be plugged in propperly, but I'm sure they're the 15 year old origional lines so replacing them couldn't hurt.

[TheNewbie]

Can't be anything else as without air won't idle that high.

Actually I figured it out today.  It was a bad seal between the intake manifold and the head.  I sprayed some carb cleaner around the top of the intake manifold and it sucked it in and bogged down the engine.  Then I put my hands up there and could feel the air sucking into the intake where it bolts to the head.

Now I know what I'll be doing this weekend.

[sharpxmen]

Actually I figured it out today.  It was a bad seal between the intake manifold and the head.  I sprayed some carb cleaner around the top of the intake manifold and it sucked it in and bogged down the engine.  Then I put my hands up there and could feel the air sucking into the intake where it bolts to the head.

Now I know what I'll be doing this weekend.

ho do you get that from replacing the waterpump though?