I have a 98 dx hatch and im having some IACV trouble, ive done all i can think of and havent fixed it yet- looking for ideas. Ive cleaned the old one, didnt help- replaced it, didnt help, bled the coolant system, didnt help, no vac leaks. I dont know what else to do. The IACV seems to be working, if I disconnect it while its running the idle flux speeds up So what else is there?

 

Stock Civic?

You didn't describe the type of idle problem you are having. Give some details.

Any CEL codes?

 

maybe your tps..mine was doing it ended up being a blown tb seal from the psi from the turbo. Also try moving your distibutor some that helped out on my somewhat.

 

yeah its pretty much stock- i only have an intake and and exhaust. Its doing the typical iacv issues. When its cold it will sputter and backfire under light throttle, usually once or twice until its warm. When its warm at idle the reves will bounce between 500 and 2000 and sometimes will feel like its going to stall. I do have a cell- #14 which is the valve. This all started after i got the car back from honda, they replaced the ignition coil

 

check your fluids in the rad that can cause it and make sure there are no bends or anything in the hoses. and the iacv is not always garanteed to work even if brand new

 

yeh IACV are hit or miss

 

blah- yeah i was thinking thats where it was heading. I really dont want to have to buy anotther one, and i got this one on ebay so i cant return it. Ill double check the fluids and hoses and what not. Thanks for the help, I really appreciate it

 

This^ sounds like a misfire or timing problem. It seems that replacing the coil has not solved the problem. Fix this problem first.

This is most likely a separate problem. A faulty or dirty IACV is only one possible cause for code 14. Pull the code with an OBD2 code reader. Post the OBD2 code.

 

ok i have some codes-
P0113
P0505
P1509

 

i'm having the same problem.. no need to open another tread when yours is already open. so i'ma just wait and see what other problems it may be.

 

If you reset the ECU, do all three codes return after running the engine?

 

that im not sure of. I just got the scanner today so I dont know if those exact codes come back but I do know the engine light comes back on. I reset it tonight and will check the codes when it comes back on, most likely that will be on the way to work tomorrow.

 

In the meantime, check whether the IAT sensor and IACV connectors are plugged in.

 

P0505 is the only one thats come back so far- I am thinking the other two were from when I was disconnecting the IACV to test it. Everything is plugged in now.