Vacuum port on rear of manifold not plugged
05-07-2012, 10:54 PM
#1
Staging Lane
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Vacuum port on rear of manifold not plugged Just recently finished with the LS1 to LS6 pcv system in anticipation of more mods in the future. This is on a 98 LS1.
When I had the intake manifold off, on the rear there are two vacuum ports, one small, one large, and the map sensor. I noticed that I did not have the rear port capped. I've had this motor swap done in 2006 and 4500 miles on the car, all without this port being capped. There's a possibility it was capped long ago and got "lost" after the tranny swap. Only a few hundred miles since the swap.
After finishing up the PCV job I capped the port. This obviously made it idle lower, however, at WOT it becomes a dog. Driving around town fine, but as soon as I really get on it, theres hesitation and feels terrible. Do I need to keep it capped and run it until the PCM relearns?
Anybody know whats going on?
When I had the intake manifold off, on the rear there are two vacuum ports, one small, one large, and the map sensor. I noticed that I did not have the rear port capped. I've had this motor swap done in 2006 and 4500 miles on the car, all without this port being capped. There's a possibility it was capped long ago and got "lost" after the tranny swap. Only a few hundred miles since the swap.
After finishing up the PCV job I capped the port. This obviously made it idle lower, however, at WOT it becomes a dog. Driving around town fine, but as soon as I really get on it, theres hesitation and feels terrible. Do I need to keep it capped and run it until the PCM relearns?
Anybody know whats going on?
05-08-2012, 12:31 PM
#3
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As far as I'm concerned its never been tuned. Since I've had the motor anyways. Its a bone stock 98 ls1 I picked up in 2002. Obviously the port needs to be plugged. Does the PCM need time to "relearn" it now that there is no unfiltered air coming in? Or do I need to tune it??
Last edited by livewire0201; 05-08-2012 at 12:38 PM.
