I just installed a K&N stock replacement air filter on my 98 4.3L and my gas mileage has taken a dive, probably largely due to my truck idling at 1000 rpm over the 600 it used to (or 500 before I replaced the spark plugs). Someone once mentioned that the K&N's don't jive well with mass air sensors, but I can't remember why. Anyone else had this problem after putting in a K&N?

And speaking of spark plugs, I replaced mine with Bosch before I knew better. Should I be concerned about the extra 100 rpm it put on the idling speed? And what exactly is so bad about Bosch? Everyone seems to agree they're no good, but I've yet to see an explanation why.

Finally, this problem I've always had, but never really looked into. My wipers sometimes like to jump to full speed on their own when I turn them on, or just keep wiping after a windshield wash for several minutes. It's never really bothered me, but since I'm begging for help anyway, has anyone else had posessed blades?

Cheers,
L.

http://www.automotiveforums.com/vbulletin/showthread.php?t=487204
read this thread. it has pics of what happens to bosch plugs in a 4.3. they break,crack,burn up, etc..

Finally got around to replacing the Bosch plugs with AC Delco--Wow!! What a difference!

I just installed a K&N stock replacement air filter on my 98 4.3L and my gas mileage has taken a dive, probably largely due to my truck idling at 1000 rpm over the 600 it used to (or 500 before I replaced the spark plugs). Someone once mentioned that the K&N's don't jive well with mass air sensors, but I can't remember why. Anyone else had this problem after putting in a K&N?

And speaking of spark plugs, I replaced mine with Bosch before I knew better. Should I be concerned about the extra 100 rpm it put on the idling speed? And what exactly is so bad about Bosch? Everyone seems to agree they're no good, but I've yet to see an explanation why.

Finally, this problem I've always had, but never really looked into. My wipers sometimes like to jump to full speed on their own when I turn them on, or just keep wiping after a windshield wash for several minutes. It's never really bothered me, but since I'm begging for help anyway, has anyone else had posessed blades?

Cheers,
L.

i installed an aftermarket performance maf, ran like crap. called tech support, first question, do you have a K&N filter. yes. when was the last time you cleaned and re-oiled it. a month ago. well, spray the maf wires very lightly with a good carb/injector cleaner and let dry, then try to get the excess oil out of the filter by re-cleaning and using lite oil followed by 2-3 hour drying without forced air/heat.. check the inside and if it feels too oily, dry it some more. the oil from K&N filter oil gets on the wires in the maf and freak it out. did what he said, and performance and gass milage came back to normal. the best the K&N did for me was 1-1.5 mpg better on a road trip from south florida to wisconsin. that real savings is the K&N doesn't get thrown out. just be frugal with the oil part.