Engine surge on reuild

[zise ex]

this is for my 1992 eagle talon TSI njust did a rebuild and it idles at 2200 and shoots up to 2400 and back down to 2200 and repeats and it stays idling like that... it has all the vacuum lines from factory and i used a diagram to hook them up, maybe i crossed two but im not sure... any input?

 

[dsmracing92]

Take some brake parts cleaner/choke cleaner and spray around the intake and the injectors seals, tb ect...... see if the engine idles up at all. If it does u have just found your leak. Idle surge is typical of a vaccum/intake leak of some sort. Also, go to vfaq.com and make sure you set your idle air control motor at zero or make sure the IAC is good. its going to be in one or the other. Also check on vfaq and make sure you have the TPS set correctly that will also make an idling issue. Does it vary from when the engine is hot to cold at all? Good luck!

 

[casperfast]

if you did a rebuild then i am going to assume you might have touched the throttle position sensor. i have seen them adjusted so poorly that they do this. an intake leak most likely will not cause a consistent surge like this. an dont do what racing 92 said about the isc at zero, read the vfaq if you choose and follow the directions. if you have a way to log then it will be adjusted at a step position, i think 30ish. but first check out that throttle position sensor, loosen the mounting screws and SLOWLY rotate it while the engine is running and id the surge changes then you might have found your problem and will want to adjust it correctly. Visual Frequently Answered Questions - Home Page click on "intake" then at the bottom of the throttle body section "TPS adjust"

 

[zise ex]

It was the iac... Now on my other talon it has all the vacuum removed to run a MBC and I have it setup like the vfaq and when it gets into boost after I let off the gas it dies... Could this be a air/fuel mixture problem? The screw on the intake has been adjusted before

 

[Simadowna119]

For the record, An intake leak CAN cause a consistent idle surge. I have seen it happen more than a few times.

As far as the car dying after boost, are you venting you BOV to the atmosphere? What mods does the car have?

 

[zise ex]

No it's recirculating... It is all stock other than a fmic and a MBC and vacuum delete. And while I'm at it the motor we did the rebuild on wont go into gear now. It went into hear perfect before but now when we try and put it into any gear it won't push in at all and when it starts to it grinds and won't let it in gear. Trans was removed and a new stock clutch was installed as well as a new slave cylinder.