7XRXSN

yeah ill have to trace those lines tomorrow and see whats missing or removed.. currently car seems to be driving and idling fine 9xx rpm steadly with those 2 uncapped .. from my experience usually open vacuum lines/leaks can cause rough idling so this is little unusual. thanks for your help ill post updates as soon as I get these cked out

7sins

open vacuum on speed density systems cause high idle. let us know.

DaleClark

iTrader: (55)

On the FD with a MAP sensor only post-throttle body vacuum leaks make any difference. Anything before the throttle body won't affect idle - if it's a boost leak you will lose boost, but the car will start, run, and idle fine. You can totally remove the intercooler plumbing and the car will run fine.

On a car with a MAF (most modern cars) they will have all kinds of funky issues with even a small leak between the MAF and the engine.

Post throttle body leaks on the FD as stated result in high idle. Large enough and the car will run crappy and have a high idle.

Dale

7XRXSN

Not sure if my idle is that high it sits around 9xx rpm once engine warms up. As I start to cap the open vacuum nipples (2 front and 2 back of the UIM after throttle body) idle starts to drop dramatically with each nipple resulting in very low idle around 3-2xx but doesn't kill the engine. When I just cap one vac nipple (front side) I noticed that it'll drop to 8-7xx .. I've been driving the car around for a few days/few miles with the vac nipples uncapped as it was for several years from previous owner seems to drive fine and boost fine as far as I can tell.. To bring idle down I capped one nipple (front side) to bring rpm to 7xx drove around for a day or 2 and seems to have no notice affect .. Now when I blip the throttle continuously I notice the lag in response.. but if gradually giving it gas between shifts or idle no noticeable lag ..

Could changing to a lighter flywheel have affect delayed throttle response?
And since the battery died for several months could that have affect on the apexi pfc? do I need to reset it?

DaleClark

iTrader: (55)

The PFC will remember its settings forever. You're good there.

It sounds like you have a non-functional ISC. You need to focus on that.

Also you have no air pump, make sure O2 feedback is disabled on the PFC or it will idle crappy and be rough on/off throttle.

I did a big thread a while back on idle troubleshooting, look that up.

Dale

7sins

could be some ding dong closed the idle bleed screw all the way as well. should be 1/2 to 3/4 turn out from full closed on a stock engine.