KOER code 13

[Haus]

I cant find any info on this code. all I know is it means Cannot control RPM during ER Self-Test low RPM check.

any info on this code.

this is the only code I get for KOEO and KOER
1992 5.0 LX

 

[HISSIN50]

Are you having idle issues? IAC issues or a vac leak are two possibilities.

 

[jrichker]

Code 13 Key on Engine running - Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)

If your idle is above 725 RPM, the computer will set this code. Normal idle speed is 650-725 RPM. Higher than that may mean that you have a vacuum leak or someone has mechanically set the idle speed by use of the idle speed screw. This effectively disables to computer’s ability to control idle speed.

 

[Haus]

I cant get the idle that low. the throttle blade is almost completely closed and it still idles High. When the motor is cold and in park. it idles fine. in gear it drops to 850 or so. when the motor is hot and in park the idle is 1200. even higher if the engine temps are hotter.when in gear, it idles fine.

the IAC is brand new. but i didnt get the exact one i needed. instead of the connector on the IAC being at a 90 degree angle. I got one that comes straight out. So i had to turn it up side down so it didnt hit the air tube.

 

[jrichker]

Most IAC's won't work properly unless you mount them just like the original stock unit. If you mounted the IAC upside down, that may be the root cause of your problem.

 

[Haus]

ok. ill pick up the right one and report back

 

[Haus]

but what i dont understand is to why it would idle fine when cold but when its warm, the idle is high. if their was a problem like vac. leak i would think it would do it all the time. not just when the motor is warmed up

 

[HISSIN50]

When it's idling high and in Park, have you tried disconnecting the IAC's electrical connector to see if the idle drops?

 

[Haus]

it goes down maybe 50-100 rpm when i disconnect the IAC. in gear it idles perfect. even tho the throttle blade is completely closed. cause i can feel it get stuck when i press on the gas pedal.

but when the motor is cold. I have no problems.

The car is running hotter then normal. Its been getting up close to the mid mark according to the gauge after only like 5-10 mins of driving. but only sometimes tho.

 

[HISSIN50]

I'd start trying to find vac leaks.

 

[Haus]

only one i havent replaced or checked is the upper intake manifold gasket. I have took the intake off and put it back on numerous times. its a felpro gasket. not sure if they compress when you put them on and have to replace them if you take off the upper manifold. So im not sure. Stock intake

 

[HISSIN50]

You should be able to reuse those, but for the few bucks the gasket costs, you might wanna replace it. I'd keep checking vac lines for cracks, etc..........

 

[Victor's GT]

Code 13 Key on Engine running - Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)

If your idle is above 725 RPM, the computer will set this code. Normal idle speed is 650-725 RPM. Higher than that may mean that you have a vacuum leak or someone has mechanically set the idle speed by use of the idle speed screw. This effectively disables to computer’s ability to control idle speed.

If one were to use an idle air bypass plate F2PZ-9F939-A, to set the idle higher than 725 or so, would code 13 still occur? Also, I see a lot of different procedures for resetting base idle....most of which say to adjust idle to "your liking"...but if your liking is above 725, one should expect KOER code 13, correct?

 

[jrichker]

If one were to use an idle air bypass plate F2PZ-9F939-A, to set the idle higher than 725 or so, would code 13 still occur? Also, I see a lot of different procedures for resetting base idle....most of which say to adjust idle to "your liking"...but if your liking is above 725, one should expect KOER code 13, correct?

No matter how you get there, setting the base idle above the computer idle limit should set code 13. The only way around this is to modify the computer's internal programming.

 

[Victor's GT]

Code 13 Key on Engine running - Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)

If your idle is above 725 RPM, the computer will set this code. Normal idle speed is 650-725 RPM. Higher than that may mean that you have a vacuum leak or someone has mechanically set the idle speed by use of the idle speed screw. This effectively disables to computer’s ability to control idle speed.

Is that 725 RPM limit with or without the IAC connected? In other words, if idle is set to 725 RPM with the IAC disconnected, when it's connected, would a code 13 to be expected?

 

[jrichker]

Is that 725 RPM limit with or without the IAC connected? In other words, if idle is set to 725 RPM with the IAC disconnected, when it's connected, would a code 13 to be expected?

Yes, if the mechanical base idle is above 725 RPM, you will set code 13. The IAC can only add air to increase the idle speed. It cannot take air away to decrease the idle speed.

 

[Mustang5L5]

Sounds to me like you have a vac leak.

With iAC unplugged and throttle blade fully shut, the engine should stall out.

 

[Victor's GT]

Sounds to me like you have a vac leak.

With iAC unplugged and throttle blade fully shut, the engine should stall out.

I'm simply trying to get the car to idle over 725 RPM (I like 900 RPM) and there seems to be my issue causing KOER code 13

 

[Victor's GT]

Yes, if the mechanical base idle is above 725 RPM, you will set code 13. The IAC can only add air to increase the idle speed. It cannot take air away to decrease the idle speed.

OK...If base idle is set at an RPM so not to get a code 13, my question now pertains to the IAC.....Let's say car is idling at 700 RPM, when turning on headlights or any other electrical load, is the IAC responsible for keeping the RPMS from dropping below 700?

 

[jrichker]

OK...If base idle is set at an RPM so not to get a code 13, my question now pertains to the IAC.....Let's say car is idling at 700 RPM, when turning on headlights or any other electrical load, is the IAC responsible for keeping the RPMS from dropping below 700?

The computer does not know about the alternator's output or load, since its internal voltage regulator operates at 5 volts. It will attempt to keep the idles speed at a steady RPM between 650-725 RPM.