i have a 2000 civic ex VTEC 1.6L SOHC.
i have a pulsing idle. up and down and up...no accessories are on.

 

Remove the intake piping and start the car. Use your finger to block the hole inside the TB for the IACV. Does it still pulsate? Get a smoke machine (or a friend who vapes), and smoke test your engine looking for vacuum leaks. Just to eliminate a faulty code reader, is your CEL on? Does it work?

 

yes CEL works

 

when i cover the

 

Replace your IACV.

 

Or do it Scotty Kilmer style and puff a cheap cigar through the brake booster vacuum line with air intake hose temporarily sealed off. Better yet, smoke yourself an Arturo Fuente 8-5-8 Natural Lonsdale. I tried this with my Civic about six months ago and it works very well.. both the test and the Natural Lonsdale.

OP.. Also, remove and clean the throttle body. It was tough to concentrate through that ****-storm of words you jumbled together in you original post but, I didn't see where or if you mentioned cleaning the TB.

 

sorry that you can't be bothered to read everything done to this point.
you're useless as a result. you can't even be bothered to read what was or wasn't done,but you suggest something.
thanks,but no thanks as you certainly are not much of a technician based on that alone.
try lawn dart advice or something. it's simpler and requires much less reading...i'm sure.

 

thank you as well.

 

Bleed the cooling system and adjust the idle speed. If the problem persists, test the ECT sensor and TPS.

 

thank you as well.

 

Did you forget to reconnect the IAT after unplugging?

 

no.

 

wondering about som

 

found bad baloney.