Fluctuating Idle when starting...HELP!!!!

[albanks]

I ran a search and really didn't find anything with any substance, hopefully one of the more technically experienced guys can help me out..

Here's my problem, Every morning when i start my car it idles very very high (2500rpm). At first i figured "ok, it's cold, once it warms up it will go back to it's normal idle which is around 500-700 rpms," but lately it hasn't even been idling there, but i'll get back to that.

As i'm waiting for the car to warm up, it's idling at 2500rpm and slowly increasing till it reaches about 3000rpm at which time the idle dips from 3000 to 500, it does this a few times and then the motor settles down and idles @ 2000rpm. This began to happen about a week ago and i have no idea what the heck it could be. A week ago i had a normal 500-700rpm idle, now my car idles @ 2000rpm, with 1500rpm being the lowest which is still too high. Has this ever happened to anyone on here? Please Help!

FYI - I drive a 1990 cb7 ex coupe with a JDM H22. I've already changed the starter on the H22 and have not done a tune up recently.

Help a brother out! Thanks!

[wrichards2005]

Its the Idle Air Control valve, read the DIY for cleaning out the screen. Do a tune up. Should run better... later.

[JDMcb7]

I just recently had the same problem with my girlfriends integra. A few things you can check, take of the Idle Air Control valve (IACV) and use brake cleaner to clean out any dirt and debris in the little screen. Don't hesitate to use quite a bit. Then, with the engine running, unplug the connector the IACV and let the engine idle for a moment then plug it back in. This re-sets the IACV. Don't be alarmed if your check engine light comes on at this point.

If that doesn't fix the problem, you need to try adjusting your Fast Idle/Thermo valve (FITV) To do this, remove the throttle body and take notice of the sensor mounted on the bottom of the throttle body. On the back (facing towards firewall) there will be a little plate with two tiny screws. Remove those screws (careful not to loose them) and you will see a white plastic plunger inside there. Take a flat head screwdriver and stick it in one of those little groves and rotate it clockwise until it can be turned no further. Install opposite the way you took it apart.

Always make sure you check that you have proper coolant levels. If these two things DON'T fix the problem, start looking for vacuum leaks. However 9 out of 10 times idle problems such as yours are related to both of these valves.

Good luck and let us know how it turns out.

[ACCLUDE91]

yup, check the idle air and do a tune-up. If that doesn't do it post back up about it.

[owequitit]

It is most likely not the IACV.

It is more likely to be one of the following 2 things:

1) I have seen cases of extreme idle misadjustment that have resulted in this problem as well, so I would try that first. It is an easy check, and eliminates the possibility of it being the problem. Follow the instructions in a proper manual and you should be fine. If you need them, let us know, and we will get it for you.

2) the Fast Idle Valve or FIV. It is located underneath the throttle body. The reason they usually go bad is because it is basically a WAX controlled valve, that expands and contracts with temperature. It seems to be more common on the JDM H22 because I am assuming that in an effort to be environmentally friendly, they drain all coolant from the cars. Because of the way the laws work over there, the engine may sit for a very long period of time without coolant (even though it would still have low miles) which would allow the wax to break down or dry out in the air, resulting in a faulty FIV.

You can either replace it (about $65 from www.hondaautomotiveparts.com) or block it off altogether. Simply cut a coke can template to put in between the TB and the FIV, then make a gasket using material of your choice. I have in the past had to fill the TB cavity that feeds the FIV as well.

The main purpose of the FIV is to raise the idle when cold to help avoid engine surging while the car is cold. It may not idle as smoothly, but the IACV will bring the idle up to normal.

This usually fixes this problem the majority of the time. If none of this works, then I would suggest looking at the IACV.

[westsideaccord]

Yes most likely FAST IDLE VALVE(aka fast idle thermo valve!) (Do a search for it)
Also check your coolant level, if its low or has an air pocket, it will do this!
Peace!

[owequitit]

The adjustment method of tightening the plunger on the FIV (it was mentioned above) is also a valid method that I forgot.

Keep in mind though that the FIV is not designed to be adjustable, so this is a TEMPORARY fix only. It might last a very long time. I have also seen it last a matter of days.

[albanks]

Thanks for the quick replies guys, i appreciate it. As mentioned i ran a search on the IAC Valve and printed out the DIY written up for it. I'm gonna attempt to do this weekend. If that fixes the problem then great, if it doesn't then i will pursue the other avenues you guys have mentioned to me i.e vaccum leak, white plunger, etc.

Again, thanks for the quick replies and i'll keep you guys updated! Gracias!

[pretty_ricky302]

i say the best thing to do is take it to a place u trust and have them runa test and then they can tell u whats wrong, b/c i cleaned the stuff checked for leaks and my car still does it, so ill just throw out a buck just to get it ova with. just another fix to an old car, just pay ya dues

[aero]

fast idle valve... i just fixed mine.

would idle around 3k when warm. Then when it started to warm up, it would get a jumpy idle until it was all the way warm, then it would idle fine.

If you have a gasket scraper in the correct size, its a perfect tool for tightening down the white ring in the FITV.

[DC4KiD]

Make sure to check your PCV Valve also.

[chaosfactor]

pcv didnt fix it but it definately made a difference

[xfactortype1]

good job guys..right on

right on guys.



FIV valve does idle for engine cold.

IAC takes over once engine reaches operating temperature

reguards tomd

[albanks]

Well...this past saturday i attemped to clean up the IAC valve. I printed up a DIY, bought the cleaner, gathered my tools and took to it.

I disconnected the plug that goes from the head to the IAC, no problem. I got the top screw loose and it came out, no problem. Now onto the second screw, PROBLEM. I couldn't get enough space in there to maneuver and unscrew that second bolt. Apparently it's too close to the stock fuel rail and there's a screw on the fuel rail that wouldn't allow me to get my ratchet in there. I though about unscrewing that bolt on the fuel rail, but again it was too close to the IAC valve and couldn't get in there.

Has anyone had this problem before? If so, how did you get around it, if at all? Please Help, this nasty idle is killing me in the pocket (gas ). BTW, it's a JDM H22 Motor.

[According2Aaron]

I had no problems with the bolts on the IACV. The only "problem" I ran into with them was that the one of the passenger's side was in a compact space and I couldn't get it with the ratchet, but I got it out with the wrench with no problem. Of course, I do have an F22A1.

Good luck.