Motor ran fine for a few weeks after getting the injector replaced, but now I have intermittent stumbling at low RPMs and I can feel misfires while holding constant RPMs (interstate driving).

Any ideas on what could be causing intermittent misfires? This is more frustrating than a dead injector which at least you can pinpoint to a specific cylinder. An intermittent misfire is, well.... intermittent (man I'm eloquent).

Steve

sounds almost like intake stumble to me.especially the stumble at constant speed on the interstate.

Stumble is also at idle, it's fine when I pull up to a stop but in about 10-15 secs the RPMs drop and it starts missing errratically.

Would a dirty MAF sensor do that?

I'm gonna try a few of these things...

http://www.twinturbo.net/ttnetfaq/FAQpages/hesitate2.html

bah

flower pot fixes all!!!!!!!!

Nothing has changed in over 6 years, had my K&N since soon after I bought the car and never had this issue. I'm thinking fouled MAS or an intermittent injector.

I guess my real question is - Do injectors failed intermittently, or just work / no work?

this is an educated guess but in theory injectors could fail intermittently. If they get trash build up inside of them from dirty gas or whatever i would assume the more gunk it gets the worse off they will be. Same with voltage, if there is corrosion on the connectors the less current the worse it would work. yet agin this is in theory.