Code 33
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FTE Legend
Joined: Jun 2004
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From: Upstate NY
Code 33
So, for a '93 F150 4x4 5.0 AOD, does code 33 indicate "EGR not opening", or does it indicate "EGR not closing", as listed in the manual that came with the Innova code reader?
Logistics Pro
Joined: Mar 2005
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From: Mexico, Missouri
I would bet "not opening". If the EGR valve was sticking open/not closing, the truck would run like crap, if it would even stay running at idle.
If the truck is running and not giving you any major headaches, I would be inclined to say it just means it's not opening.
If the truck is running and not giving you any major headaches, I would be inclined to say it just means it's not opening.
Lead Driver
Joined: Jan 2019
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From: N.W. Alabama
I would bet "not opening". If the EGR valve was sticking open/not closing, the truck would run like crap, if it would even stay running at idle.
If the truck is running and not giving you any major headaches, I would be inclined to say it just means it's not opening.
If the truck is running and not giving you any major headaches, I would be inclined to say it just means it's not opening.
Lead Driver
Joined: Jan 2019
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From: N.W. Alabama
I thought , my bad, scroll down it will start with 2 digit
Ford OBD1 Codes and Procedure Fuel Injection Transmission (Mechanics)
Ford OBD1 Codes and Procedure Fuel Injection Transmission (Mechanics)
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FTE Legend
Joined: Jun 2004
Posts: 31,796
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From: Upstate NY
I thought , my bad, scroll down it will start with 2 digit
Ford OBD1 Codes and Procedure Fuel Injection Transmission (Mechanics)
Ford OBD1 Codes and Procedure Fuel Injection Transmission (Mechanics)
Lead Driver
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From: N.W. Alabama
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Fleet Owner
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From: Kentucky
There are two parts to running the KOEO tests and Stored Code display. The first are the Key On Engine Off (KOEO) tests. If there are no flagged issues you will get System Pass Code 11. If there are issues flagged the corresponding code is displayed. Once that is completed your code reader will usually display Code 10, this is a misinterpreted code for the separator flash between the KOEO tests and Stored Code display (also referred to as Continuous Memory). After the separator flash any codes in CM will be displayed. If there are no stored codes then System Pass Code 11 will be displayed.
Since you did see Code 33 displayed from Continuous Memory it means the EGR valve opening was not detected during one or more drive cycles.
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FTE Legend
Joined: Jun 2004
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From: Upstate NY
Thanks, that is just about as I remember it. I first got code 11, then code 10 and then 33. I wasn't aware of the distinction between KOEO and stored codes.I put a hand vacuum pump on the EGR and it seemed to hold vacuum and when I released it I heard the valve close. So, I guess it is down to a broken vacuum live or solenoid?
Lead Driver
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From: N.W. Alabama
I chased my green EGR vacuum line crack down, finally, was in the black wire loom, so I cut the green line and left about 4" on both ends used 7/64" gas line and took short cut through upper intake and finally, code left
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FTE Legend
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From: Upstate NY
Sounds like a good approach.
Lead Driver
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From: Houston/Sugar Land
If you will run your test again and unplug you jumper or reader when the codes begin it should clear that code. Of course you would want to make sure it cleared by running the test again now. You didn't mention if you had a CEL or not. If you did see if it comes back you can start checking things or if you were just testing for codes you can check after running a few times. This information in better detail is available in your reader manual page 37..Sandy
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FTE Legend
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From: Upstate NY
Thought I would get back to this. I put vacuum on the EGR to prove function. Then changed out the tubing going to it from the solenoid, still had code and CEL. Replaced solenoid and code stayed clear and no pretty lite on dash. Thanks guys.
I did come across a decent write up on another forum for this type of repair. Fairly exhaustive. Rubber Vacuum System Replacement (5.0\5.8 EFI) - Ford Truck Club Forum
I did come across a decent write up on another forum for this type of repair. Fairly exhaustive. Rubber Vacuum System Replacement (5.0\5.8 EFI) - Ford Truck Club Forum
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Oct 2, 2009 11:18 PM