I've had these idling problems since a new intake manifold and converter were installed.

I'm trying to figure out if the idle problems are due to the intake the manifold or the converter.

I have checked for vacuum leaks around the intake but could not find any.

Here's what the idle does. Start the car cold idle surges 500-1000rpm until it's warm. When I stop and the car is in DRIVE it will surge about 800-850rpm. BUT if the car is in PARK it idles almost perfectly smooth.

Why would it not idle right in DRIVE but idle fine in PARK once the car is warm.

So what do you guys think vacuum leak or crappy idle that needs a tune.

 

I had a simular problem when i installed my BBK manifold. Did u use the throttle body gasket that comes with the bbk intake?? I did and it wasnt quite right, u have to cut a hole in the gasket for the ''idle control valve'' i think is what its called. It lets more air into the intake when u first start the motor cold.

 

I did use the gasket it came with, i'll have to check that, I didn't modify the gasket at all. Thanks.

 

After I put my converter in if I cam to a hard stop or pulling in my garage my rpms would surge like you are mentioning, even stalled once. Turned the idle up a little bit and no problems anymore

 

I raised the idle on mine about 50rpms it helped the car start without dying. But didn't fix my surging.

 

Ok, it's dark out and I'm using a single flashlight but I got the throttle body off and your right the gasket doesn't have the hole cut in it, if this fixes it your my hero.

 

I hope it fixes ur problem or atleast helps. I installed my intake last summer and didnt notice a problem until winter (cause in Nebraska it goes from summer to winter in like 4 hours). But anyway over winter I would try to start my car once a week just to keep the fluids moving. But it would hardly run, once it started to warmed up alittle bit it would start to smooth out. I thought my tune got really screwed up some way. Toward the end of winter I decided to port my throttle body and thats when I noticed the gasket problem.

 

Same exact issue here the colder the weather the harder starting it was and I could smell it running rich. I'll find out in the morning if it fixed the cold start issue, which bothers me way more then the surging at stop lights. Thanks for taking the time posting, this is my daily driver and it will help a lot to have it fixed.

 

Well if it is the problem dont get to mad @ BBK, afterall they do make mostly mustang parts. haha.. I really like my intake hope you do to..

 

Looks great and differently helps at higher rpms. I suggest it to others but now I'll make sure to tell them about the gasket, haha.

 

Car starts great now, no crazy surging. But when in DRIVE and stopped it still surges about 50rpms. When in PARK it idles fine. Any ideas on why this is happening?

 

You need to get it tuned, one because the extra airflow coming in from the intake and second because the less interia mass from the smaller converter. The ECM was programmed to account for the extra mass, since you remvoed it, the idle control needs to be re-worked (kind of like a cam). Do not adjust you idle set screw, as the ECM uses an IAC valve to allow extra air in while idling, all that will do is possibly throw a code. The ECM will still bring the idle at the programmed rpms. Good luck!

 

Yeah id have to agree. Its probably a tuning issue caused by the converter. But it sounds like fixing the TB gasket solved most of ur problems, so if u can live with a little surge just wait till ur next round of mods to get it tuned.

 

I ordered hp tuners pro a couple days ago. The idle seems to have fixed itself though no more surging at stop lights, now when I start the car it will go to like 1500rpms when I put it in gear but after it gets warm it'll drop down to 750-800rpm.