89 f150
Fleet Owner
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
Code 33, is not a KOEO code.
ER 12 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test upper limit band.
ER 33 in Key On Engine Running indicates that the EVP sensor input did not change after the EVR solenoid was instructed by the processor to open the EGR valve. Because a Code 84 was not received in the Key On Engine Off Self-Test, it is known that the EVR solenoid functions electrically. It is also known that the EVP sensor is in the expected closed valve range because Code 32 and 34 were not received in either Key On Engine Off or Key On Engine Running Tests.
ER 13 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test lower limit band.
ER 25 indicates that the Knock Sensor (KS) signal to the processor was not sensed during the Dynamic Response Test after the ID code in Key On Engine Running Self-Test.
Looks like a bad Idle Air Bypass valve.
Here all the names of the same item:
•Idle Air Bypass
•Idle Air Control
•Idle Speed Control
•Throttle Bypass Air
•Idle Bypass
•Inlet Air Controller
•Inlet Air Bypass
•Intake Air Bypass
•Intake Air Control
ER 12 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test upper limit band.
ER 33 in Key On Engine Running indicates that the EVP sensor input did not change after the EVR solenoid was instructed by the processor to open the EGR valve. Because a Code 84 was not received in the Key On Engine Off Self-Test, it is known that the EVR solenoid functions electrically. It is also known that the EVP sensor is in the expected closed valve range because Code 32 and 34 were not received in either Key On Engine Off or Key On Engine Running Tests.
ER 13 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test lower limit band.
ER 25 indicates that the Knock Sensor (KS) signal to the processor was not sensed during the Dynamic Response Test after the ID code in Key On Engine Running Self-Test.
Looks like a bad Idle Air Bypass valve.
Here all the names of the same item:
•Idle Air Bypass
•Idle Air Control
•Idle Speed Control
•Throttle Bypass Air
•Idle Bypass
•Inlet Air Controller
•Inlet Air Bypass
•Intake Air Bypass
•Intake Air Control
Thread Starter
|
Fleet Mechanic
Joined: Aug 2008
Posts: 1,446
Likes: 9
From: NE Iowa JD Country
Code 33, is not a KOEO code.
ER 12 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test upper limit band.
ER 33 in Key On Engine Running indicates that the EVP sensor input did not change after the EVR solenoid was instructed by the processor to open the EGR valve. Because a Code 84 was not received in the Key On Engine Off Self-Test, it is known that the EVR solenoid functions electrically. It is also known that the EVP sensor is in the expected closed valve range because Code 32 and 34 were not received in either Key On Engine Off or Key On Engine Running Tests.
ER 13 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test lower limit band.
ER 25 indicates that the Knock Sensor (KS) signal to the processor was not sensed during the Dynamic Response Test after the ID code in Key On Engine Running Self-Test.
Looks like a bad Idle Air Bypass valve.
Here all the names of the same item:
•Idle Air Bypass
•Idle Air Control
•Idle Speed Control
•Throttle Bypass Air
•Idle Bypass
•Inlet Air Controller
•Inlet Air Bypass
•Intake Air Bypass
•Intake Air Control
ER 12 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test upper limit band.
ER 33 in Key On Engine Running indicates that the EVP sensor input did not change after the EVR solenoid was instructed by the processor to open the EGR valve. Because a Code 84 was not received in the Key On Engine Off Self-Test, it is known that the EVR solenoid functions electrically. It is also known that the EVP sensor is in the expected closed valve range because Code 32 and 34 were not received in either Key On Engine Off or Key On Engine Running Tests.
ER 13 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test lower limit band.
ER 25 indicates that the Knock Sensor (KS) signal to the processor was not sensed during the Dynamic Response Test after the ID code in Key On Engine Running Self-Test.
Looks like a bad Idle Air Bypass valve.
Here all the names of the same item:
•Idle Air Bypass
•Idle Air Control
•Idle Speed Control
•Throttle Bypass Air
•Idle Bypass
•Inlet Air Controller
•Inlet Air Bypass
•Intake Air Bypass
•Intake Air Control
Thanks appreciate your efforts!!....I'll pass along this new information.
we did clean the Idle Air Control (AIC), it was very gunked up, but the interior plunger was moving, just laden with carbon... but prior to the tune up he was experiencing a high idle, just not as high as it is now. To clean it we remove the AIC from the engine, then removed the solenoid from the AIC, sprayed it thoroughly with carb cleaner, let dry, then reattached the solenoid and returned it to the engine.
Is there a right or wrong way to reattaching the solenoid on the AIC?? the O-ring looked good, no cuts or anything. & the gasket to the upper intake was appeared good as well.
Secondly~ when reattaching the whole AIC to the engine, the solenoid faces towards the radiator yes???....that is the only way we can see that that can be installed incorrectly....pretty sure that is the way it came off.
thanks again for all the help
Senior User
Joined: Aug 2009
Posts: 142
Likes: 0
From: Wylie,TX
Does FORD call the IAC by all of these names? Or is it just us types?
I knew there were 2 names but 9? WOW Almost sounds like we're getting into human body part naming here.
Here all the names of the same item:
•Idle Air Bypass
•Idle Air Control
•Idle Speed Control
•Throttle Bypass Air
•Idle Bypass
•Inlet Air Controller
•Inlet Air Bypass
•Intake Air Bypass
•Intake Air Control
/Ricache
I knew there were 2 names but 9? WOW Almost sounds like we're getting into human body part naming here.
Here all the names of the same item:
•Idle Air Bypass
•Idle Air Control
•Idle Speed Control
•Throttle Bypass Air
•Idle Bypass
•Inlet Air Controller
•Inlet Air Bypass
•Intake Air Bypass
•Intake Air Control
/Ricache
Thread Starter
|
Fleet Mechanic
Joined: Aug 2008
Posts: 1,446
Likes: 9
From: NE Iowa JD Country
Thanks appreciate your efforts!!....I'll pass along this new information.
we did clean the Idle Air Control (AIC), it was very gunked up, but the interior plunger was moving, just laden with carbon... but prior to the tune up he was experiencing a high idle, just not as high as it is now. To clean it we remove the AIC from the engine, then removed the solenoid from the AIC, sprayed it thoroughly with carb cleaner, let dry, then reattached the solenoid and returned it to the engine.
Is there a right or wrong way to reattaching the solenoid on the AIC?? the O-ring looked good, no cuts or anything. & the gasket to the upper intake was appeared good as well.
Secondly~ when reattaching the whole AIC to the engine, the solenoid faces towards the radiator yes???....that is the only way we can see that that can be installed incorrectly....pretty sure that is the way it came off.
thanks again for all the help
we did clean the Idle Air Control (AIC), it was very gunked up, but the interior plunger was moving, just laden with carbon... but prior to the tune up he was experiencing a high idle, just not as high as it is now. To clean it we remove the AIC from the engine, then removed the solenoid from the AIC, sprayed it thoroughly with carb cleaner, let dry, then reattached the solenoid and returned it to the engine.
Is there a right or wrong way to reattaching the solenoid on the AIC?? the O-ring looked good, no cuts or anything. & the gasket to the upper intake was appeared good as well.
Secondly~ when reattaching the whole AIC to the engine, the solenoid faces towards the radiator yes???....that is the only way we can see that that can be installed incorrectly....pretty sure that is the way it came off.
thanks again for all the help
Thread Starter
|
Fleet Mechanic
Joined: Aug 2008
Posts: 1,446
Likes: 9
From: NE Iowa JD Country
Iac
Ok they took "it" , the IAC, off and double checked a couple of things.
with it removed...looking at the ports to the intake....then turn the key on and could see the plunger move and return with turning the key off.
so they are second guessing which way the solenoid should point when installed on the intake.
does it , the solenoid of the IAC, point toward the rear of the engine or to the front???
they think it was on the toward the front
we tried a spare IAC from my ranger....wasn't sure if it was good or not. any-way....the port sizes are sizeably smaller from the ranger....but it did help bring down the RPM's on a idle a bit ...but still way to high. As before, as soon as you put it into gear (Auto) it drops RPM almost to normal....is this still the a IAC problem
with it removed...looking at the ports to the intake....then turn the key on and could see the plunger move and return with turning the key off.
so they are second guessing which way the solenoid should point when installed on the intake.
does it , the solenoid of the IAC, point toward the rear of the engine or to the front???
they think it was on the toward the front
we tried a spare IAC from my ranger....wasn't sure if it was good or not. any-way....the port sizes are sizeably smaller from the ranger....but it did help bring down the RPM's on a idle a bit ...but still way to high. As before, as soon as you put it into gear (Auto) it drops RPM almost to normal....is this still the a IAC problem
Fleet Owner
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
These codes say that the computer could not control the rpm of the engine.
When a computer can not control the RPM it is most of the time the IAC valve or the wiring from the computer to the IAC valve. That is what I was going by.
High RPM most of the time is caused by a vacuum leak. This vacuum leak could be anywhere from a bad brake booster, a bad vacuum hose going to any solenoid or part or a bad intake or throttle gasket.
When a computer can not control the RPM it is most of the time the IAC valve or the wiring from the computer to the IAC valve. That is what I was going by.
High RPM most of the time is caused by a vacuum leak. This vacuum leak could be anywhere from a bad brake booster, a bad vacuum hose going to any solenoid or part or a bad intake or throttle gasket.
Thread Starter
|
Fleet Mechanic
Joined: Aug 2008
Posts: 1,446
Likes: 9
From: NE Iowa JD Country
These codes say that the computer could not control the rpm of the engine.
When a computer can not control the RPM it is most of the time the IAC valve or the wiring from the computer to the IAC valve. That is what I was going by.
High RPM most of the time is caused by a vacuum leak. This vacuum leak could be anywhere from a bad brake booster, a bad vacuum hose going to any solenoid or part or a bad intake or throttle gasket.
When a computer can not control the RPM it is most of the time the IAC valve or the wiring from the computer to the IAC valve. That is what I was going by.
High RPM most of the time is caused by a vacuum leak. This vacuum leak could be anywhere from a bad brake booster, a bad vacuum hose going to any solenoid or part or a bad intake or throttle gasket.
just was concerned if there was right and wrong way to reattach the IAC.
thanks again
Fleet Owner
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
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