Recently bought a 94 del Sol Si that has the original d16z6 in it. At around 1400 rpms it will stutter until about 2000 rpms. It's throwing the code for IACV. I've replaced it and it still has that code. I'm completely stumped at what it could be. Please help!

 

I haven't had a check engine light on an EG civic, but I know other warning lights (i.e., SRS and ABS) need to be reset once a repair has been made. If this is true with a CEL, were you able to reset it after replacing the IACV?

Also, how old is your coolant, and what level is it at? If it's old, try flushing the system and refilling with fresh coolant. Make sure to bleed the system after filling your radiator.

Lastly, Take a moment to check all of your vacuum lines. I've had a similar issue that was caused by a small hairline crack/tear in a vacuum line... Best of luck!

 

I have a 94 EX that's doing the same thing. I noted the vacume line running from the intake had a huge hole in it which I have already fixed. I'll check all other lines and see what I can come up with and post back here if it fixes the problem.

Shanasman12

 

Did the OP ever figure out what was wrong? I have my valve cover off right now to have the threads taped, replace the gaskets, and paint it but when I get it back on if it does the same thing as before I would like to know where to look.

 

You could check the FITV below the throttle body. The valve could be stuck and needs to be cleaned, and/or adjusted. This happened to me before. After cleaning and adjusting it, the idle became stable to its original rpm around 750-800, and it didn't stutter when it reached 1200-2000 rpm. I was a happy camper and never had another problem with it. Good luck

 

You need to unplug the battery for a few minutes to reset the ECU. Turn on the headlights with the battery unplugged to discharge any residual charge in the system. Then turn them off and rehook the battery. Drive around for 10 minutes to re-learn the ECU, and then wait for a few days, then rescan for codes.

 

You have any pics of where you're talking about. Googled with no results.

Shanasman12

 

Problem had finally been fixed. After trying almost everything, it turned out to be switched sensor plugs. I'm guessing whoever had the car before me must've screwed it up taking them off. Thanks for all the help!