Civic082382

My check engine light came on and now sometimes at idle the cars rpms jump between .5k to 1.2k while its in drive (it automatic) but when i get done driving i put it in park it starts doing it right away. i also notice it does it when i'm moving with out having my foot on the gas petal. i have no idea what would be doing this, i checked the spark plug and wire and the air filter it is all clean. the car starts with no problem but after about 5min of idle it starts up while in park!

Any info please would help

Update 05/31/09 4:56pm
Just got the code P0505 Idle Control System Malfunction

So anyone got anything on this i can check?

update 06/01/09 11:16am

When i got the car this line was blocked off, and the hose was just laying there. so i thought it pluged into this port on the intake manifold. was i wrong? what is this port, i never saw this before?

bigD

what code is it throwing

Civic082382

not sure haven't gotten it to a shop to see, i don't know if the car would die on me i'm tring to check all the common stuff before i drive it there

bigD

you dont need to drive it anywhere https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/engine-swap-info-faqs-how-ck-engine-lights-878010/

Civic082382

Just got the code P0505

Idle Control System Malfunction is what the code stands for so anyone got any ideas what i can do here? and when does that check engine light go out?

civic_driver

You can start with checking the IACV for proper voltage and the wires going to it for any burns, shorts, wire cuts, etc.

Former User

With the warm engine idling and the intake removed, cover the lower port leading to the IACV inside the throttle body with your finger.

1) If the idle speed does not drop, you have a vacuum or intake air leak.

2) If the idle speed does drop, try to adjust the idle speed with the idle screw on the throttle body. If the idle speed cannot be adjusted, replace the IACV.

Civic082382

you happen tou know what the right voltage is?

Former User

If you have P0505 and a high idle, then follow the instructions in my previous post.

shailoche

+1 on the IACV...

If it checks out then look into the Fast Idle Thermo Valve.

Former User

There's no FITV on the stock D16Y8 engine.

civic_driver

I just looked at the service manual and here are the possible causes for P0505:

- IACV mechanical malfunction
- Throttle body clogged port, improper adjustment
- Intake manifold gasket leakage
- Intake air hose loose leakage
- Vacuum Leak
- ECT (Engine Coolant Temperature) sensor incorrect output
- Throttle Position sensor incorrect output

So you don't have to check for proper voltage on the IACV even though it won't hurt if you do.

Former User

P1508 and P1509 indicate a problem in the IACV circuit.

P0505 typically indicates an intake air/vacuum leak or a mechanical problem with the IACV.

royaltrex7

follow this its the first thing to do. If you have a vacuum leak get some starter fluid with the spray straw, and spray around all vacuum hoses. If you get a high idle. Bada boom...... there is your vacuum leak.

Civic082382

all good INFO thanks so much i'll be hitting this up ASAP now will the check engine light go out or do i have to reset some, and where is that rest button?

royaltrex7

to reset you could always just disconnect the battery eat some dinner hook it back up everything should be cleared might run rough at first though

Former User

The CEL will continue to illuminate until you fix the underlying cause of the problem, which is likely a bad IACV or an intake air/vacuum leak. When you have fixed the problem, then clear the ECU. This can be done by removing the 7.5A BACKUP fuse under the hood for a few minutes. If the problem is repaired, then the CEL will no longer be triggered by code P0505.

Civic082382

Thankyou all good info

SoHcEK99

I had the same problem for the longest time and could not figure it out. I went through all the steps that everyone has already listed. It turns out that the throttle cable was too tight, and it was causing a small vacuum leak at idle. I loosened it up, reset the cel and everything's good now.

Civic082382

updated the thread

Civic082382

bump

Former User

The disconnected hose goes to the fuel injection air control valve:

Civic082382

i think i'm missing something cause there is nothing else disconneted just that hose was laying there and the tube sticking out of the manifold was capped off. I hate this motor so much i miss my b series! all this OBD 2 **** is a pain

Former User

What tube sticking out of the manifold? The FIA receives air from the air cleaner.

civic_driver

It seems like your FIA Control Valve was removed. You need to get a new one and run it the way it's shown in Ron's post. Right now you have plugged the hose coming from the intake straight to the injectors. What you need to do is insert the FIA Control Valve in between.