my 99 prelude is idleling real bad. one thing i know dats bad right now is that my knock sensor is broken and that i got a vacum that kinda broke. it comes out this little black box under my intake manifold and goes to this other little place on the firewall with other hoses bigger than it. could that b the problem???

 

any vacuum leak will make it idle like that

that box is a vacuum tank for the 2ndary butterflies under the IM

 

and how can i fix it?? becouse it broke off from the part that goes to the firewall. on the part where it gets thin.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by h22prelude99 &raquo;</TD></TR><TR><TD CLASS="quote">becouse it broke off from the part that goes to the firewall. on the part where it gets thin. </TD></TR></TABLE>

I don't follow what you are trying to say. Do you just need new vacuum line or is there an actual broken component? I know knock sensors can be a little pricey but you should probably fix that as well. When you say your car idles "NASTY" what do you mean exactly? High idle, bouncing idle, rough idle, car is smoking at idle?

 

im assuming you are running the stock air intake, or you would have had that VAC box removed and plugged the line on the back of the manifold.

you can first try just plugging the vac source on the back of the manifold, just follow the tube from that box you are talking about to the manifold and cap it off. see if that is your problem.

i dont really know if the knock sensor is necessary. im not really sure if you can just close the circuit on the plug and leave it or not. but its worth giving a try if its already broken.

 

It would help a lot if you could take some pictures of the areas you're talking about because your English is pretty bad and hard to understand.

 

Fix your vacuum leak first. After that clean your IACV and FITV. You can do a search here and find out how. Also do a basic tuneup. Let us know how it goes.

 

Yeah a vacuum leak makes idle real bad I know first hand.