New Member: Already have a problem. :) IACV/throttle body issues

[RandomAg]

Hey guys. New member here. Recently got rid of my 97 Del Sol with a lackluster d16y7, and picked up a near-stock 03 ep3(came with a no-name short ram intake w/ K&N filter.

Been lurking a bit, but I plan on properly introducing myself/setting up a build thread.

This site has been more than helpful already. By simply using the SEARCH BAR and READING, I've learned a crap-load about my new(ish) toy.

However, I ran into a snag recently: I've been having occasional problems with the IACV while driving on the highway(CEL came on/felt like a vacuum leak.) Shutting off/turning on the car would fix the problem for a bit, but it was getting annoying. So, last week I decided to clean my IACV.

After re-installing the IACV, the car constantly threw up a CEL and acted as if there was a vacuum leak. (I can't even drive the car to autozone to get the CEL scanned.) So, I've obviously mucked something up. I decided to cut my losses and just buy a new IACV.

Installed the new IACV yesterday and disconnected my battery to reset the ECU(probably a stupid choice, in hindsight). Now, when I start the car, it idles super rough, then the revs start bouncing between 1-2.5k and there is a knocking/rattling sound coming from the engine head. No CEL is coming up(...yet, I assume that's because I disconnected the battery during the install.) Could I have messed up one of the other sensors? KPRO would be a dream right now, lol.

Any help or insight would be GREATLY appreciated! If I need to divulge any more info about the situation, let me know. Thanks to student loans, I don't think my wallet could deal with the pounding it would receive at the hands of a mechanic...lol

Thanks for reading!

[Nickle n Dimin]

idk maybe idle relearn if you haven't done already.. someone will have the correct answer for ya on here hang in there

[RandomAg]

Thanks! I'll try that when I get home.

Funny thing is, my Del Slow was having IACV issues when I sold it. I didnt want to deal with the hassle of replacing the valve, so I knocked a couple bucks off the asking price. This is my Karma...haha

[MajorJones]

When i first got my ep, it was doing the same thing. I replaced my IACV but no luck. I then drained the radiator and put new fluid in making sure that no air bubbles would get trapped in there. Since then i've never had the issue again. Hope its the same for you, best of luck!

[RandomAg]

Two things to try when I get home. Thanks guys!

[RandomAg]

Just borrowed a scanner and got home. CEL came back on. Throwing up codes P0303, P0304, P0300: all related to misfires, if I'm not mistaken. I changed the spark plugs two weeks ago. I'm going to go check for vacuum leaks again.

Side Note: If I don't post again, its because I was arrested for firebombing my local autozone. Those guys nearly sent me into a violent rage today.

[RandomAg]

Yesterday, I found a vacuum leak on the TB. Fixed it, drained/filled coolant, and did an idle relearn. Car was stuck in limp mode until I drove it a mile or so, then it magically started running smoothly! It could be placebo, but it feels better than when I got it. (could be the new IACV + cleaned TB, too). No more clicking noise coming from the head, and it seems to be idling smoothly.

However, while the CEL stopped flashing, it is still on. Reading misfires on all cylinders, and it wont let me erase the codes. Thoughts, anyone? I'm going to drive it for a day or two and see if it resets itself. Hopefully no more problems pop up.

Thanks again, guys! Even with just two replies, this thread saved me $$$! Just needed a push in the right direction. Now to use the money I saved to find some OEM side skirts! ;)

[beechstreet]

What plugs are you using? Are all of the coil packs connected properly?

[Nickle n Dimin]

that's great that you found the vacuum leak. and checking the plugs couldn't hurt before you start driving regularly again. it could take alot of miles before it resets, if at all.

[RandomAg]

Just put in some new NGKs about three weeks ago, but you're right. I'll check them tonight.

[Draw7Seven]

I once read "when something goes wrong, start by checking the last couple of things that you "fixed"..." I'd definitely check those plugs over and all the connections. Since all cylinders are reporting misfires, I'd bet that they all share the same common problem: something about the procedure you used to reconnect each coil pack or perhaps a lose connection further up the line?