Dionili Securio

My 03 accord randomly idles low as hell, 500 rpm and sometimes as low as 400 then stalls ( very rarely)

I have swapped the iac twice, replaced TPS and MAF I've also removed and cleaned the throttle body and checked the Iac's leads for voltage and bled the cooling system of air

Sometimes it feels as if the car does not adjust for any electrical load, like i can start the car and it will idle normally, then start the ac and the idle will drop to 500 and not come back up i've tried adjusting the idle to handle this but it eventually goes back to how it is. ive notice idle also drops for lights and radio/amp

I've also been able to drive as normal with ac on....with seemingly no issues then come back to the car after parkinging then bam...low idle


somtimes it idles just fine then ill pump the gas and instead of the idle coming back to normal it drops below 500 and turning the ac off/ loads off does not affect the low idle...

I dont know what else to do.... car has 200k miles
Edit: Car does periodically throw low idle code, then it goes away when car is working... then comes back..,.
maintenance light is on used to come on flashing but stopped
Get an ELD?

New throttle body?

/HALP

Thanks guys.

Also, i have noticed that i can start the car and when it does idle fine it will stay that way untill i touch the throttle then it will drop like a rock

Dionili Securio

I'll bump this with some more information....

I did replace the alternator to, and i had the battery tested. i realize when the RPM drops the volts drop as well...today when stopping at a light then pulling into a parking space the rpms dropped and i just happened to have torque open and saw the volts stayed at 12.2 even when i rev'd the engine for a while....then returned to normal and the rpm went up


This is driving me nuts. I have a suspicion that i might have a bad eld.... or a stuck TB....Any advice will be welcome as i'm about to drop a few hundred on parts to fix this when i have my brother install new CV's

buying:
TB <really want to avoid spending 85$ on a new tb, when i have allready replaced all sensors on my current tB and it seems to be operating fine

Intake hose, mine was torn at the coupling to the tb, still stays on. pretty sure it cause high idle if it was leaking

eld...running out of ideas considering i replaced the IAC 2x and verified theirs voltage at the IAC wires...

ANY help would be appreciated...i know theres a honda guru here that knows the solution to my issue.

This is gonna be my daily driver/bass wagon....i really need this engine sorted so i can work on speakers/pick up a project car.... this has been holding me up 6 months and a good 1200$

Dionili Securio

Ugh,,,,welll looks like either no one knows whats up or dont give a **** enough to answer...

So i guess ill throw another 500$ worth of parts at this thing and hope i fix the issue. i'm out of troubleshooting steps....

DCFIVER

You need to scope the IAC command and response to and from the ECU.
Additionally the the relevant data PIDs regarding load should be monitored in the scan data, to see what is occurring and why.



***A proper diagnosis would have cost far less than $500 at a good shop***

Dionili Securio

I actually got into a fight with a mechanic at a local shop after he could not diagnose my car but still wanted me to pay 150

I aint cheap by any means but i'll be damned if i pay someone to fail with out at least prior notice


I need to aquire a scope and ill get one soon.

As for now i have a mutli meter and a scantool, what can i do?

Dionili Securio

I'm pretty sure this issue is coming down to the cheap as dirt IAC's i have been buying from amazon for 18.99 upon checking the reviews i can see that they fail on an almost consistent basis and most dont work out of the box or have resistance fluctuations

That being said i'm going to purchase an IAC from a more reputable source and report back to how it works.

Dionili Securio

Too Any and all who have experinced a similar issue.

Turns out the 22.99 iacs i bought (now three) were all garbage i bought a 59$ iac from intermotor and all my issues vanished...

YOU GET WHAT YOU PAY FOR! DONT SKIMP ON THE IAC AND INTERMOTOR ROCKS!