I have posted a few times already on this truck and yesterday I had the chance to pull codes. I just bought the truck and since I bought it I have replaced the following items: plugs and wires, cap and rotor, fuel and air filter. It runs pretty good except for a miss at idle and what seems to be fairly poor mileage. Below are the codes I got. I was wondering where I should start with these codes?

KOEO:

3 2 7 3 2 7 1 3 2 7 3 2 7

KOER:

4 1 3 2 7 1 2 9 1 6 7 5 3 6 6 3 2 then it repeated same codes again.

The way I read them is 327, 129, 167, 536, 632

Is that correct? If so, what do they mean? I have the code list but not sure where to proceed. Thanks in advance.

Brian

 

You have to look at the spacing between the codes. There's a longer blink between codes than there is between digits in a code.

Typing them all out in a long string makes it next to impossible to read.

Also, since you haven't posted any details about the truck, such as year, model, engine, or transmission, or even the reason that you pulled the codes to begin with, it's going to be quite difficult to help you.

 

Sorry, realized I didn't give vehicle info after I submited the post. It is a 1991 F-250, AT, 2wd, 351, 108K mileage.

The codes came out like this. This is first time reading codes so I am not sure if they are correct.

KOEO:

3 2 7
3 2 7
3 2 7

KOER

4
1
327
129
167
536
632

Let me know if that makes sense or if I should test them again?

 

129, 167, 536, and 632 are due to things you didn't do during the engine running test. The single flash after the engine code 4 is your cue to blip the throttle, touch the brake pedal, and press the over drive switch. Those codes just mean the computer didn't see what it was expecting to see during the test. Most likely, the only code that is important is the 327 for EGR position below minimum voltage. You're definitely reading the codes correct! Now that you know the computer expects some input from you during the test, you should be good to go next time.

 

Ok, if then I am only getting a code 327 where should I start looking to diagnose the problem. Last night I pulled the IAC and the EGR and cleaned them. I am not sure if it did any good because the miss at idle is still there. How do I test the IAC to see if it is working properly? The miss at idle is really the only thing bugging me at the moment. Also, is there any way to check the EGR system to see why it is throwing a code? Thanks in advance.

Brian