Code 16 any help?

[Kami808]

My truck is a explorer 1991 sport 4.0 ohv
I have reset the computer and cleared the codes many times and I'm still getting this code 16 - RPM to low to perform o2 sensor/fuel test. I have replaced my o2 sensor 2 months ago with little miles on them, Anybody knows what I can do to fix it? Thanks.

 

[MrShorty]

I sometimes think that the first step to diagnosing some of these codes is getting a code list that you trust. My code list (and I don't really know how good it is) suggests that, on a '91 with an electronic, distributorless ignition, that a KOEO 16 points to a fault in the IDM circuit. Is your 16 a KOEO code or a CM code? Your description suggests a KOER code, but my code list does not say anything about a KOER 16.

My suggestion would be to identify your code as a KOEO, CM, or KOER code, then get a good code list (see if your local public library has print or internet subscriptions to professional manuals) and get good, reliable definition for the code.

 

[Kami808]

I sometimes think that the first step to diagnosing some of these codes is getting a code list that you trust. My code list (and I don't really know how good it is) suggests that, on a '91 with an electronic, distributorless ignition, that a KOEO 16 points to a fault in the IDM circuit. Is your 16 a KOEO code or a CM code? Your description suggests a KOER code, but my code list does not say anything about a KOER 16.

My suggestion would be to identify your code as a KOEO, CM, or KOER code, then get a good code list (see if your local public library has print or internet subscriptions to professional manuals) and get good, reliable definition for the code.

Yes this is a KOEO code and the code list I got it from here:
http://www.explorerforum.com/forums/showthread.php?t=227663

another thing when engine is cold at idle is at about 1200 rpm then warm it drops at 700rpm which it run very rough.
also I have replaced all the old sensor which all are new and no different with old and new

 

[natenkiki2004]

That is extremely weird. I've never seen "Ignition Diagnostic Module" mentioned before. Maybe your ICM is going out?

Do a KOER test and see what you get.

 

[FR-425]

KOEO CODE 16 and IDM are for cars only.

KOER code 16 requires driver input at the correct time. (depress throttle to 100% for 1 second) Your scan tool prompts you when to perform brake, throttle and steering movements and can take some practice to get it right.

Sounds to me that you are not performing the test correctly.

If you are getting code 16 while driving. You will need to clear codes using the scan tool, not just disconnecting the battery.

This happens when the test mode is not properly exited.

This is a common glitch with the "paper clip" method.

 

[Kami808]

That is extremely weird. I've never seen "Ignition Diagnostic Module" mentioned before. Maybe your ICM is going out?

Do a KOER test and see what you get.

OK here the codes I got:

KOEO:16, 66
KOER:11

I did the KOER test correctly 3 times which it gave me the same code 11 system OK.

KOEO CODE 16 and IDM are for cars only.

KOER code 16 requires driver input at the correct time. (depress throttle to 100% for 1 second) Your scan tool prompts you when to perform brake, throttle and steering movements and can take some practice to get it right.

Sounds to me that you are not performing the test correctly.

If you are getting code 16 while driving. You will need to clear codes using the scan tool, not just disconnecting the battery.

This happens when the test mode is not properly exited.

This is a common glitch with the "paper clip" method.

The way I clear codes I pull off the jumper wire while the key is on (test mode)
which it I'm not using any scan tools I'm doing it by paperclip method test.

 

[MrShorty]

Here's the code list I tend to use, and I'm not even sure that it is right all the time: http://www.troublecodes.net/Ford/ I would still start by getting something you trust to tell you what a KOEO 16 is. FR 425 seems familiar with the KOEO 16, so I will defer to his expertise.

The KOEO 66 I have seen before, and it is an MAF code. Assuming this is KOEO and not CM (you don't distinguish between KOEO and CM codes), I would also inspect your MAF and circuit.

 

[Kami808]

Wierd this code is telling me that my ICM is not working properly?

I tested my MAF sensor with a multimeter its getting a good signal also checked connection and wires seems all good.

 

[Kami808]

First of all I was a little confused about the IDM code, I did some research now I can understand it more that I'm going to do some diagnosing first the best i can do before I buy a new PCM or a ICM.
Any Suggestion where to start looking?

 

[Kami808]

Fixed!

It's been a month now but I could found where the code was coming from I couldn't believe my new $200 ICM that I brought in August was acting weird I also found my coil pack and ECM has no ground this might have burned my ICM, now that i fixed my ground connections I connected my old ICM everything fixed no more code 16. Thanks to all who came in here to help!

 

[mekelly]

Advanced Auto can check your ICM for you. I don't know if it's 100% accurate but it should flag a defective unit. It's worth doing before you run out (I know you already have) and buy a new ICM.