My friend asked me to look at his 1996 accord LX, 2.2L, auto/trans. because it revs up and down after reaching normal operating temperature. Here's what I've done so far:

- Verified it was not low on coolant
- Removed, cleaned and adjusted FITV by screwing down clockwise until snug
- Started the engine and allowed it to reach normal operating temperature
- Placed my finger over the hole (7:00 position) in the throttle body and verified the FITV was closed because no vacuum was present.

After doing all this, the car still revs up and down. Also, I want to mention that warm or cold, the engine skips and I don't know if it may be a vacuum leak in the right place causing these symptoms or a bad power steering pressure switch. Any ideas anyone?

 

Check for intake air leak; PCV stuck open, brake vacuum line disconnected, or intake manifold leak.

I would also clean the idle air control valve (IACV), throttle plate, and throttle bore w/ throttle body cleaner. A sticking IACV or throttle plate might cause this problem also.

good luck

 

Thanks TexasHonda for the info. Today I started the engine and discovered an intake manifold air leak next to the no.1 cylinder by spraying carb. cleaner where I kept hearing this annoying hissing sound. I also tightened one of the bolts near the leak which was loose as well. I mean, as soon as I sprayed the carb. cleaner between the manifold and the engine, the idle corrected itself in respect to the misfire at the no.1 cylinder. However, it had no effect on the revving up and down issue. Now as far as I can tell, this is the only leak on the manifold and it seems that maybe, just maybe I could use some sort of sealant on it to close it up and perhaps avoid having to remove the manifold. As for the revving up and down, after I read your post I started the car, let it warm up to operating temp., disconnected the IAC valve (air cleaner off) and the idle dropped very noticeably, which meant my IAC is working in that respect.

Again, if you think there is a way to seal the manifold without having to remove, it please let me know.

Thanks a bunch,

Hondalover

 

I think trying to glop some kind of sealant around the manifold is just looking for trouble in future repair work. Unfortunately, that means remove the manifold & install a new gasket. Kind of a PITA but not the worst job I can think of.

Then when that's fixed, set your base idle, reset your ECU & force it to re-learn.

 

Torque the bolts on the intake manifold and see if that eliminates the air leak.

As for the changing idle, remove the snorkel from the throttle body. Start the engine and allow engine to warm to operating temperature. Cover the lower port inside the throttle body with your finger. If the idle stabilizes, then something is up with the FITV.

You already cleaned and tightened the FITV. You may want to remove the FITV and clean out the coolant passages. Also clean out the coolant hoses going to and from it.

 

Looks like nobody mentioned that you should bleed out all air pockets from the cooling system. That can confuse Honda's idle-control system.

 

Ok, the car does not skip anymore after replacing the intake manifold and plenum gaskets. I aslo cleaned the IAC valve with carb. cleaner until the spray ran out clear. Then I bled the cooling system and tried to reset the ECU by disconnecting the neg. battery cable and waitng at least 30 seconds.

As for the revving up and down idle, when I first started the car it idled at 1000 rpm and as it approached normal operating temperature it rose to 2000 rpm. So I manually pulled the throttle back until it hit the stopper and the revving up and down reappeared at 1000 rpm. Then I manually revved the car up an down at the throttle body, pulled the throttle back to the stopper and the revving up and down went away.

Now, in my earlier post I mentioned that i cleaned and adjusted the FITV and throttle body. It seems to me that my trouble may still be in the throttle or mabye an idle adjustment is needed because after doing this, I turn off the motor and restart it and the initial idle is 2000 rpm and drops to approx 1250 rpm at normal operating temp. (fans running). If anyone can give me any ideas it would be greatly appreciated.

 

You need to set the base idle. JimBlake has posted that procedure on here before. See: https://www.hondaaccordforum.com/for...ad.php?t=35858

 

I just looked at that post PA linked. My instructions include pulling fuse #13 to reset your ECU. That's only 98-02 so for your year you can either pull the battery cable or you can look up which fuse (back-up or whatever it's called).

 

Ok, just wanted to let everyone know that the car is no longer misfiring and is idling fine all the way around now. Seems like I had to just wait it out after manually working the thrrottle back and forth. Thank you all for your help; You guys are great!