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7/02/2026 9:45 AM  #1


Code reader codes and test sequence. 66 EFI 302 Coupe auto

I seem to have a lot of questions lately so please forgive me.
Just when things were going well, my 66 efi 302 is now cutting out while cruising. I plugged the code reader in and got the following codes 11-10-18-33-51-96. all KOEO.
Code 18 made me check the timing and the spout. The distributor was a bit loose so I checked the timing and set it at 10 degrees and cleaned the spout with a bit of brake cleaner and ran the car. I thought it was ok until it stalled again after a long run. I tried the code reader with KOER and the car revved up, i checked timing which was now 30 degrees and then cyl 8 came up and it died. Tried again and it started showing codes of which one was 44 but I missed any others while getting a pen but now when trying to run the test it revs for a while throws up cyl 8 and dies. Does this sound like a distributor/spout problem? I replaced the distributor innards about 4 years ago when it just died suddenly and would not start until I replaced the hall sensor.
Love this car but it is testing me somewhat.


Bullet Bob equipped car,
 

7/02/2026 3:25 PM  #2


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

My take on it is that its shotgunning codes at you.  It "knows" something is wrong, but can't define it exactly.  

Code 11 is system test pass
Code 18 is a spout code, which could mean a couple things, but loss of PIP signal is one of them
Code 33 is an EGR code, I'm assuming the EGR is not present
Code 51 is ECT circuit open
Code 96 is fuel pump circuit open
Code 10 is a cylinder #1 balance test failure, meaning that cylinder #1 isn't contributing to power
Code 44 is another emissions code related to the AIR system, which I'm guessing is no present

Some of these codes could be the result of a bad ground somewhere (open circuit codes).  I would check all your grounds just to be safe.  

After that I'm guessing we can disregard codes 33 and 44, because you aren't running emissions equipment.  

To me the most important code are 18 and 10.  This would seem to indicate a possible ignition problem.  I think I would start by checking the PIP signal.  
 

 

7/02/2026 3:45 PM  #3


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Thanks for the response. You're right in that i'm not running emissions equipment.
I figured it was either pip or fuel but was leaning towards pip more. I know that the earth on the engine is good as I made a heavy duty earth from the block to the chassis. I did have a spare TFI module so I changed that and it made no difference. I will take a look at checking the pip signal.
If I get a new distributor on this 5.0 HO what drive gear do I need?


Bullet Bob equipped car,
     Thread Starter
 

7/02/2026 7:58 PM  #4


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Does the fuel pump cycle and stop with Key On Engine Off?

If it does not, I would check that first along with all ground connections as mentioned.

Do you have the ground from engine wire harness at the rear of intake manifold?

 

7/02/2026 7:59 PM  #5


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

 

7/03/2026 2:04 AM  #6


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Hi, yes, fuel pump seems to be ok and is still running for a second after the engine quits although I intend to replace the Fuel Pressure regulator as it is the original one that came on the engine so no idea how old it is. I do also have a new fuel pump that I will install.
Thanks for your reply.


Bullet Bob equipped car,
     Thread Starter
 

7/03/2026 5:02 AM  #7


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

I've always liked an adjustable regulator on those engines.  I'm trying to remember the one I put on the 331 going into my '89.  I'll be up in the shop later and take a look and post back.  

 

7/03/2026 9:28 AM  #8


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

If anyone can recommend a kit for the distributor or a distributor I would be very grateful. My distributor number is:E4ZE-12131-AA. I looked  at Rock Auto but couldn't find a distributor so maybe someone can recommend a pip.
Thank You.


Bullet Bob equipped car,
     Thread Starter
 

7/04/2026 8:34 AM  #10


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Here are some choices.
Notice the additional cross reference part numbers that can also be used.





 

7/04/2026 3:32 PM  #11


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Thank you. I have ordered two of them as the one in my car had done less than 20 miles.


Bullet Bob equipped car,
     Thread Starter
 

7/04/2026 11:42 PM  #12


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

I really like this code reader for OBD1 stuff. No more counting flashes.
https://www.innova.com/products/digital-ford-code-reader-1981-1995-3145
 

Last edited by 50vert (7/04/2026 11:43 PM)


"Those telephone poles were like a picket fence"
 

7/05/2026 7:01 AM  #13


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Innova makes good code readers.  I have a model that reads OBD2 codes that I really like.  

 

7/12/2026 4:28 AM  #14


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

So... I ordered two sensors from Rockauto which arrived very quickly and thought my troubles were over. I fitted the new pip sensor to the distributor and refitted the distributor, started up and set the timing. All good for about twenty seconds and then its like someone turned off the ignition. Restarted and ran fine for about two minutes and then again its like the ignition was turned off. 
So it cant possibly be the pip as this is the second one in less than twenty miles. Must be something else.
I did notice that the distributor had lots of up/down play in it so I shimmed the shaft to the correct spec but that has made no difference.
Any ideas before I start trawling through wire diagrams and chasing grounds and resistances?


Bullet Bob equipped car,
     Thread Starter
 

7/12/2026 5:12 AM  #15


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Are you sure the ignition switch is good?  

 

7/12/2026 6:56 AM  #16


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

I suggest checking the wiring and any connectors installed between the ignition switch and the PIP.  
Check both the male and female sides for any poor connection between the two, clean as necessary.  


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

7/14/2026 3:09 AM  #17


Re: Code reader codes and test sequence. 66 EFI 302 Coupe auto

Thanks for the help so far, really appreciated.
I have checked all connections and run tests for grounding faults but nothing found so far. The "Run" feed for the block of four relays is fed from the ignition switch and the relays live is direct from the battery (switched by the relay). TKO said about the ignition switch being bad and as its 60 years old, I will change it as a precaution. I know the relays are for power, fuel pump, ignition, but what is the fourth one for?


Bullet Bob equipped car,
     Thread Starter
 

Board footera


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