Idle surge & cracked exhaust manifold

[LoTekGuru]

I've only had my Talon for about a month and it has pretty bad idle surge. I read somewhere on this forum that a cracked exhaust manifold can cause idle surge. My question is, is the crack I'm seeing cosmetic or is the manifold a solid piece of metal so the crack I'm seeing is most likely all the way through, and could be causing a small leak which in turn could be causing my idle surge?

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[andymoraitis]

I'd have to say that those are likely pretty serious, but if you want to be sure, you can unhook the vacuum line from the BOV to the intake and suck some Seafoam through the line. If the cracks are all the way through, it'll pour smoke. Also, since those leaks are before the O2, your performance is getting killed. I'd look into replacement right away.

Andy

 

[v2ner]

Either way, the cracks are only gonna get bigger. You should start looking around for a stock 2G turbo exhaust manifold. I haven't heard of cracked exhaust manifolds causing idle surge but somebody correct me if I'm wrong. Good luck.

 

[pitbullowner_2]

hi i'm new to the dsm world just bought one yesterday n e ways my car has idle surge also i was just wonderung what it could be i was reading and you said that it wasnt from a cracked manifold what do you think it is please email me back for help @ [email protected] thanx alot

 

[nc90awd]

I would replace the BISS screw and o-ring. That cured my idle surge problems even though DSMs are bad about that.

 

[pitbullowner_2]

how much does that cost and where is it located also what tools do i need

 

[nc90awd]

its about $6.00, you can get them from slowboy racing and you will need a flathead screwdriver. I think its under oem parts. Its round screw by the thottle body on the intake manifold

 

[pitbullowner_2]

thanx so much this surging is making me mad....i'll let you know if it stopped, otherwise we go for the next thing and work my way down till it gets fixed

 

[pitbullowner_2]

when i replace the biss screw how far should the new one go in

 

[nc90awd]

you screw it snug, sometimes they back out and fall out. Yours may not even be in

 

[pitbullowner_2]

i have no idea where to look i look around by the intake manifold and the throttle cable but couldnt see the biss screw

 

[Nelsons91AWD]

Yea definely replace that with a nice ported 2g Mani at the least.

2g exhaust manifold

and your idle surge could definetly be your ISC causing the rough idle, very common with our dsms.

DSM ISC motor

www.ebay.com

you can get both things mentioned above

2g manifolds run around $75 for reference.

Good Luck

 

[nsxwidebodied]

it might be the tps sensor that is out, and those cracks might look cosmetic and not deep, but i were you i would just get a nice 2g manifold.........

 

[pitbullowner_2]

where is my biss screw located i cant find it anywhere please someone help with detailed directions

 

[femmeDSM]

Here is a link with a "checklist" of things that can cause idle surge.
If you could describe a little better what it's doing, we may be able to point you in the right direction. At the very least, I would check your ISC motor, TPS, BISS, and clean your throttle body (you can do this with the unit on the car, but for a more thorough cleaning, I would take it out -- i believe you need to take it out to remove the ISC anyway).

http://www.dsm.org/how-tos/tttt/tttt3.html

 

[femmeDSM]

Also here is a link to a picture that shows where your BISS is located. It is circled in purple in the image: http://members.shaw.ca/dsm.1000q/Engineprimer/1G/throttlebody.htm

 

[pitbullowner_2]

alright that helped alot but should i take the screw out and what should i check for also when i put it back in how far should it go

 

[pitbullowner_2]

i fixed it, it was just the biss screw thanx so much everyone for all the help all i had to do was tighten it up a little

 

[nc90awd]

No problem

 

[femmeDSM]

Glad it was something simple

 

[PaulN]

And might I recommend picking up a set of manuals:

http://www.ecanfix.com/~manualcd/


These are invaluable when it comes to all things DSM repair.

Also, be sure and check out www.vfaq.com and the 1000 most asked questions under the tech section of this website.

And finally the search button above will find an answer to nearly any trouble ever experienced on these DSM's. I haven't been dissappointed yet with my search rresults and I have been using it quite abit with me swapping engines and all.

Good luck!

 

[pitbullowner_2]

how far should the screw go down becues it idles to low and sounds like it is going to die

 

[femmeDSM]

here is a good VFAQ on properly adjusting the BISS. http://vfaq.com/mods/BISS-1G.html

In my experience, you will need to play around with it a little to find the "sweet spot" -- there's a certain spot that your car will like to idle at, just gotta find it.

Also, thought I would mention -- if a few days after you adjust your BISS, the idle surge comes back, it might be time to replace the BISS o-ring. You can buy this from Slowboy Racing -- air will escape out of the cracked/non-existant/deteriorated o-ring and cause all sorts of idle issues. Just something to keep in mind in case your problem persists

 

[1992TSiAWD]

Is the idle problem cured, or it stalling out on you?

Let me know, thanks.

 

[pitbullowner_2]

well i tighten it all the way then it wanted to die on me then i adjusted it till it idles at about 750-800rpm it sounds a better like it not choking as much as it was. but i tried to back the screw all the way out and it just wouldnt come out so i cant tell if the o-ring is bad or not any suggestions on how to get the screw all the way out, it just seems like there is more thread but it doesnt come out anymore