What is the normal idle? I am usually only several hundred rpms. I noticed this after adding the plenum on top of the cats.

It doesn't idle rough and I don't believe I have any leaks. Curious if this has happended to others.

 

bump

 

I believe that after warm up the Z should idle around
650+/- 50 rpms. I have the Crawford plenum and did not see a change that I can remember.

 

Tap the throttle at idle and see if the car wants to die (or does die) as it returns to idle. Try it with the A/C both on and off. If it does it prolly has a leak somewhere. Otherwise it may just be your "warm" idle you are noticing. I dont remember exactly about the idle as I have mine set at 775 to remove the bumpy stock idle.

 

It doesn't seem to want to die, it just seems a little lower. When it's warm it's about 100 rpms higher. Cold, it's 300+ rpms, hot, its over 500.

If TS had the 2004.5 ECU done, I would have it fixed with that.

 

Did you replace the small bolts on the inside of the plenum. If I remember correctly there are two of them......make sure they are snug....do not over torque them.

 

Yes, all holes were filled with bolts. It's not sputteringg or dieing or anything. It's just that the overall rpm idle seems a couple 100 rpms lower. I wonder if there's a way to do a throttle body adaptation.

 

Have you tried an ECU reset ? You know doing the river dance on the gas pedal style . The procedure is in the manual.

 

No, maybe I should try that.

 

If you unplugged the TB or disconnected the battery when installing the plenum, the service manual does call for a TB resetting procedure to be done. This is posted along with the ECU resetting procedure on Technosquare's website. Timing is everything when doing this.

http://www.technosquareinc.com/350reset.htm

 

wow -- 300 rpms?

when my Z's cold it idles at about 1250, then lowers as it gets warm to around 700-750rpm

 

That sounds about right for the G as well. Winw, don't forget that the first line on the gage cluster is 500 rpm's and not zero rpm's. If you're just a few clicks above that, you'll be at 700 rpm's and not 200 rpm's.

Also, I unplugged the connector to the TB on the plenum install and never reset the ECU. No problems with my 2004.5 6MT at all. Are you sure that the plastic ring around the oil cap is not caught beneath the plenum and allowing a slight amount of air to enter the plenum?

 

Okay, now I feel like a total dumbass. Maybe it's not as bad as I thought.

 

Don't worry about it....just glad to hear you don't have a problem.