Driving it off the cliff

[blue62]

Originally Posted by Stl-986

Easy one...No mods I'm one that keeps things pretty stock with engines.

Never feel the misfires. I can see them in durametric but that's it.

I would call idle lumpy. It isn't hunting like what happens on lawn mower engines.

Here is the weird thing. When the car is cold at startup the SAI turns on as it should. During this time that the SAI is on there are NO misfires. Which indicates an air leak to me but I would expect to see misfires on more then just bank 1.

I need to pick up a better vac gauge. The only thing I have right now is the gauge on a mity vac which I dont think is all that good or accurate.

So RPM kinda rises and falls at idle.
If you sit in neutral and hold the RPM at 1500-2000 does it smooth out???

SAI injects air into the exhaust. Misfires occur in the cylinders.
So no relationship between the two.

Maybe no misfires on cold startup because it is on a richer open loop fuel map.
So possibly the richer fuel mixture is compensating for the unmetered air of a vacuum leak at first startup.

You can get a vacuum gauge at places like O'riellys for around $25.00
Try to get one with as big a face as possible.
Also some still show the green zone, late ign. time area, late valve timing area.
But they are getting hard to find. Not many people use them anymore.
Everyone has got to the newfangled smoke machine. They only tell you one thing.
Vacuum gauge if you know how to read the needle can tell you a hell of alot.