running bad after mani mod

[ray666]

okay so i installed an isis manifold i managed to get the car running but it sputters really bad at idle and i can't get it to smooth out. i back tracked everything i've done and havn'e had any luck finding anything. any ideas?

[PyR0NiAk]

Sounds like a vacuum leak of some sort...

[ray666]

i wonder if the 3 sources on the bottom aren't sealed all the way.

[PyR0NiAk]

De Ja Vu. I know I just answered that exact question. You used the plugs that came with it, right? The elbow (on the back of the mani) that goes to the PCV or a loose coupler is more likely to be your problem.

[ray666]

yes i used that swivel elbow. what did you use? i noticed that when i pinched the hose that goes to it and the idle got a little better.

[PyR0NiAk]

Sounds like it has a leak... I used one I got from someone else. My original one came apart.

[ray666]

looks like a trip to lowes or a.a.p

[PyR0NiAk]

I really doubt Lowes has the thread pitch you need in that size fitting... I know they don't here.

[ray666]

(haven't used that in a while) any ideas where i could get one?

[ray666]

i thought it was weird that elbow swiveled. leak was the first thing i thought of when i installed it but went with it anyways.

[ray666]

update- so i replace the swivel elbow and it still runs bad. i just got my iacv and intake mani gasket in the mail i will install these tonight. i'll let you guys know how it went. if this doesn't work i don't know what else it could be.

[OM3GA]

Hmm, make sure your fuel rail is tightened down all the way. Did you also torque everything to spec? like the manifold to chassis?

[ray666]

i got held up so i couldn't get everything done last night. i will check the fuel though. i unscrewed the 3 sources on the bottom of the mani and i noticed how super easy they were to come out. maybe more plumbers tape perhaps

[ray666]

i retaped the 3 sources, replaced the iacv gasket, and tightened down everything again... its still running like s***. i'm gonna check the couplers and retape the sources for the fpr and bov.

[ray666]

so i retaped and replaced the intake gasket. still with no improvement. i'm lost guys. what else could it be? could a bad ground make it run bad?

[OM3GA]

Sure a bad ground could make it run bad, what about your throttle body gasket or the vacuum ports on it. Make sure all spots you are not using are plugged up if you have not already.

[ray666]

i replaced the throt gasket. the only open areas are the unused coolant ports. what a nightmare!

[USMCgetsome]

hate to say it but put back on the original manifold and see what u get then. Ensure you mark all the vacuum lines and if it leaks with the original manifold then at least you know your not crazy and it has to be a bad isis manifold.

[ray666]

yeah i might have to... this sucks.

[OM3GA]

I dont think that is going to solve the problem. It sounds like something is not sealed, What did you torque the mani bolts to? and is the fuel rail bolted down completely and you can tell that it is sealing? If there is a leak around there it could definitely cause that problem.

[PyR0NiAk]

There was an issue with someone's isis mani on here a while back that was cut wrong around the IACV. It was causing the IACV to behave incorrectly..

[ray666]

i guess i can do the car cleaner thing to check for leaks. as far as torque specs i just tightened until i couldn't. i remember that thread too. im gonna try one more time then i will put the stock mani back on and if it runs good again then i will know i have a bum part.

[ray666]

well i got the running enough to do some carb spraying and found nothing but i ran once i got to the iacv. i had trouble putting that on the manifold when i first put it on and when i replaced the gasket. like one of the holes was aligned.

[USMCgetsome]

pics? you might want to clarify a little more. Keep in mind this forum will only be as good as the details you provide us

[PyR0NiAk]

Yeah the bolt pattern for the iacv is off on all of the isis manis... a lot of people resort to a block off plate and remove the iacv. This, of course, causes an abnormal idle, but its definitely manageable.

[OM3GA]

Yeah i dont run IACV's

[ray666]

crap...ill just put my stock one back on. at least ill know it works. and ill ask ken if he can give me a store credit or something.

[OM3GA]

That is BS, the ISIS mani is one of the best knockoffs out there.

I can't believe it would be that. Try it without the IACV. Make a block off plate. I have an extra if you want it.

[ray666]

sure ill take it.if you're offering

[OM3GA]

Im willing to sell it cheap haha. I just think it is a better way to go.

Let me know what you think, you can email me directly at [email protected]