Mindcore

I had a great drive today, and the car ran beautufully..

But.. when I went to leave today, the CEL was on.. so I tightend my gas cap, and reset the ECU.. let it sit for a few minutes, then left.. the idle was between 1500 ang 1900 waaa wooo waaaa woooo waaa wooo.. me, the sound from the exhaust was murder.

I had a good feeling that if I had turned my car off, then back on it would have fixed itself.. but stuck on rutherford, and then the 400 I didn't want to chance it.. so I just lived with it, while confirming that my dealer could check the code for me when I got home..

That was the funny thing, after I reset the ECU, the CEL was still on..

So I get to the Dealer, and they tell me I need a new IAC valve.. whats that I ask? its an Idle Air Control valve.. whats that do I ask?
dunno, but you need one to fix the problem..

so there ya go, two CELs in about 2 months.. I am so happy I got the extended warranty..

I will say, after I restarted my car, it idled perfect, and felt perfectly fine.. its just a pain in the ass..

If you guys know what the IAC is, I'd be interested to know

matrix

Gas cap....

Mindcore

I knew you were gonna say that!

matrix

It's my standard answer to all CEL threads...

Mannn

heh heh heh

xviper

The idle air control is as the name would suggest. It regulates the engine's idle speed by letting just the right amount of air into the intake. It would NOT be unlike you using the gas pedal to regulate the idle speed. The ECU tells the IAC solenoid to let more or less air in to set the rpm based on the engine's need. eg. After a cold start, the engine idle needs to be elevated somewhat to prevent stalling until the throttle body warms up a bit. If this IAC solenoid cannot respond to the ECU's commands, then your idle speed cannot be regulated and it'll be whatever it was last set at. Although it is the main component that manages idle, other systems also come into play to affect idle rpm as well, so you may find even with a non-functioning solenoid, the idle rpm can still vary.
Besides the MAP sensor, it has been reported that the IAC is the next most noted malfunction that contributes to wonky idle speeds.

MOTU

[QUOTE]Originally posted by Mindcore

Nabs 79

Yeah, IAC's are a common problem on hondas. I had to check and change that on my b18c5 motor. If you have the helms manual for S2ks, you should be able to check the codes yourself and confirm what the dealer told you.

Siepel

Mindcore,

I believe it's the thing next to the MAP sensor on the throttle body (not sure though) or in that neighborhood anyway.

If the CEL stayed on after reset (which is impossible) it in reality means that after the initial check of the engine, a continuity error was immediatly diagnosed (surely you know this is either a shortcut or broken wire). Reading your post about the intermittent problem, I'd check the wires and connecting plugs around the throttle body area carefully; it could just be a loose connector!!!

Take care!


Siepel

PLYRS 3

[QUOTE]Originally posted by xviper
The idle air control is as the name would suggest.