I have a 1993 Honda Civic Hatchback DX. I just recently swapped out the d15 and swapped in a d16y7 from a 96 DX. When i had the d15 in the car my idle was doing the humpty dance (idle jumps from 1.5k to 2.5k). i switched the d16 over to obd1 from obd2. So on the d16 i added the following from the d15. intake manifold, dizzy, injectors, alternator, ecu, and wiring harness. The d16 is now in and this motor is also doing the humpty dance. the only thing that makes it idle normal is when i unplug the iac valve. there is enough coolant to the manifold, i cleaned the iac valve, there are NO vaccume leaks. So does this mean i have a bad iac valve and should order a new one? PLEASE HELP!!!! thanks in advance.

 

why did you do that for why not just a z6 :1

did you check the gaskets ? if your sure that you have no leeks then just go and get a iacv watch out they cost ~200.

 

blled your coolant lines

 

just because i got the motor for a good price and i thought it would fix the idle....

bleeding the coolant lines wont do anything...it did it with both motors which are useing the same intake manifold with the same iac valve thats why i think thats what it is...so its not the coolant lines

 

like I said if you think that everything is in order just get a iacv and see what happens. if it doesn’t fix the problem try and get your money back, and start over again.

 

Or I have an iacv that works for 35 shipped

 

or that.

 

Are you using the Y7 throttle body? If so that is also a problem.

 

nope using the d15 throttle body..got an iac valve off ebay..waitin to see what happens

 

I have this problem on my GSR in my Del Sol. What is PROBABLY the problem is that you have a bad Idle control valve I think is what it is called. you can try to have a shop clean it but chances are you will not fix it that way. its easy to fix it. I actually have a spare if you want to get it off of me. Lemme know.

Preston