rpms lagging before coming to idle
#21
Mine does the same thing after the intake swap. I know its a leak. The intake I bought came with the brake booster hose and it had a different plastic part on it and thats what causes the leak in mine because the one on mine has a in and out connector and the new intake actually has a T connector w/one pointing out with no cap on it. Obviously causing the leak there!
#23
Mine's been doing the same thing after my last tune (both not coming down untill I get to a stop and hanging after I rev while stopped and moving). Also becomes quite a bit worse when AC is turned on (I barely use it now because it wants to stall so much with the AC on from a stop and almost feels dead). Assuming this is a tuning problem only, could it be fixed by a tuner (other than the original one) without affecting the performance of the tune? I think the current tune is great with AC off, it's just the formentioned problems I'd like to get rid of. Thank you!
#24
Thread Starter
TECH Apprentice
iTrader: (5)
Joined: Dec 2005
Posts: 362
Likes: 0
From: lake in the hills, il
i think i might have an idea what it is.. i was just reading something about the idle, and drilling a hole into the blade of the throttle body, and i realized, i put on a p&p throttle body, and the hole was epoxied... can this be causing this>????
#25
In order for the tb to have the affects that you are having, the only thing i can think of is that maybe you forgot to put the small o-ring under the iac sensor when you installed the sensors. I have had a couple people forget to put them in and it casuses a vacume leak. If the epoxy wasnt drilled out enough then you would have the oposite affect, the car would idle low. You definetly have a vacume leak.
#26
Originally Posted by GTObsessor
Mine's been doing the same thing after my last tune (both not coming down untill I get to a stop and hanging after I rev while stopped and moving). Also becomes quite a bit worse when AC is turned on (I barely use it now because it wants to stall so much with the AC on from a stop and almost feels dead). Assuming this is a tuning problem only, could it be fixed by a tuner (other than the original one) without affecting the performance of the tune? I think the current tune is great with AC off, it's just the formentioned problems I'd like to get rid of. Thank you!
#27
Originally Posted by Smokin87TA
In order for the tb to have the affects that you are having, the only thing i can think of is that maybe you forgot to put the small o-ring under the iac sensor when you installed the sensors. I have had a couple people forget to put them in and it casuses a vacume leak. If the epoxy wasnt drilled out enough then you would have the oposite affect, the car would idle low. You definetly have a vacume leak.
Mine had hanging idle, and it surged pretty bad when I forgot that O-ring.
#29
Originally Posted by 99kamarokid
which sensor, the upper or lower one?
#33
TECH Fanatic
iTrader: (8)
Joined: Oct 2005
Posts: 1,419
Likes: 1
From: Holland Twp/Milford, New Jersey
Originally Posted by SSpdDmon
The PCM. There are two tables that add airflow that can throw off idle. Throttle cracker and throttle follower. If you revs don't come down fast enough right after you get off the gas and put the clutch in (or after you rev the engine), then it's a problem with your throttle follower settings in the PCM. If you're coasting along with the clutch in and the idle will not drop until you come to a stop, that's the throttle cracker table. Chances are though, this is an issue with unmetered air entering the engine (ie vacuum leak) since you're still on the stock cam.
#34
Originally Posted by sdm1234
wow that's great information! both circumstances happen with my car, after I got it tuned. however, what if i'm coasting along with the clutch in, and the idle stays high AND bounces between 1400 and 1900 until i come to a stop?