hit 4k rpm secondary twittering?

[quikSHOilver]

When I rev it to 4k and secondary would open and close continously causing bucking or twittering like, when I back off throttle it will idle smooth no problem... I am stratching my head on this one.

 

[quikSHOilver]

update

I disonnected the secondary vacuum and closed the vacuum port and revved it to 4k same thing it bucks... so I try clean maf with berryman then try again same thing but wont go back to idle only to stay 2k now ha what now? I did unplugged ISC it went down to 800 rpm, plugged back and idle went back normal then rev it same thing bucking then stay at 2k... whatgives?

 

[Mr Anonymous]

Sounds like a vacuum leak somewhere.

 

[midnightauto]

not sure on a gen 1-2 but a gen 3 will not free rev the rpm's bounce at the rev limiter

 

[whiteman_01]

MTX will rev to red line, where as atx will only go to about 4000 rpm's.

 

[Mr Anonymous]

I just re-read your post. It sounds like you're just hitting the park/neutral rev limiter.

But, if the car isn't stalling when unplugging the IAC then you're still probably looking at a vacuum leak.

 

[quikSHOilver]

yeah, I recently found out why it was just because of rev limit on atx thur searching the forum so all is well... and as for rough idle, found a silcone coupler wasn't sealing well so replaced the clamp and it purrs now. Thanks guys for ur input!