ETC Engine Fail Safe Mode - looking for advice - JoeGR input always appreciated!

[xford]

Had my 2006 V8 w/ 92k miles go into "ETC Fail Safe Mode" yesterday after about 50 miles of driving with some stop and go traffic in mild temps here in CA. It happened shortly after a quick stop (turned car off for about 5 minutes) and I felt a brief shutter just before. Good news was I was only a mile from home so I drove slowly back.

After about 5 minutes I re-started and the car and it shuttered again for a brief period but no codes etc w/ idle back to normal. Today, I drove the car about 25 miles without incident or noticeable missing etc.

Having been around LVC a while and reading prior posts I assume likely culprits are - Coils, Throttle Body, Electronic Throttle Control or Mass Air Sensor. Or possibly just some one off random electrical glitch - I do have an SCT Tune from Torrie on the car. I went to Midas today and we ran the OBD with zero codes stored (it appeared to me they had a high end quality reader).

Since I have 92k miles would you suggest I replace all the original coils as an initial step because I am due anyway or have a stress test done? I assume a stress test would best be done at a Lincoln dealer if they have the proper equipment? I changed my plugs in July 2012 to Denso Iridiums with 100k plus lifespan and have since put less than 20k miles on the road so I am not sure if I should do those as well (understanding a failing coil(s) can do damage). I find on e-bay 8 Motorcraft DG-529 coils for around $400 (not sure if I can trust e-bay based on a few prior bad experiences) and Rock Auto has them for around $47 each. Assuming you agree as a good first step any other suggested sources for a reasonable deal on OEM since I want to stick with Motorcraft?

Thanks in advance for any input/suggestions.

 

[jjcool00]

A Joe response from a prior post:

To be clear here, your message center said "ETC failsafe"? You can't reset that, but you can dismiss the message. (Turning the car off and back on will reset failsafe mode.)

ETC failsafe occurs when the PCM thinks that it can't control the throttle or when it can't be sure what position you have the gas pedal in. It goes into failsafe mode where power is greatly limited to insure that there is no unintended or uncontrollable acceleration.

What triggers it?

There are three gas pedal position sensors. If they don't all say the same thing (within reason), ETC failsafe is triggered. Note that RF noise from a bad coil might make the PCM read the wrong value for one or more of these sensors.

There is a throttle position sensor. If it says the throttle is in a different position than the PCM wants it to be in, then ETC failsafe is triggered. Again, RF noise from a bad coil can cause a false position reading.

There is the servo motor that moves the throttle. If it can't move the throttle to where the PCM wants it, then ETC failsafe is triggered. Often with the LS, RF noise is the problem. However, maybe this time the throttle really stuck. It's possible that it froze up in the conditions that you were in. Interestingly, there is actually an OBD code for iced over throttle. I wonder if it would come up if you had the codes read?

 

[joegr]

Had my 2006 V8 w/ 92k miles go into "ETC Fail Safe Mode" yesterday after about 50 miles of driving with some stop and go traffic in mild temps here in CA. It happened shortly after a quick stop (turned car off for about 5 minutes) and I felt a brief shutter just before.
...
Since I have 92k miles would you suggest I replace all the original coils as an initial step because I am due anyway or have a stress test done? ...

Yes, I would very strongly suggest that you replace all coils (COPs) and spark plugs (sorry). Make sure the plug gaps are correct (1.0mm). RFI noise from a marginal COP can cause false ETC codes. Your symptoms certainly sound like this could be the problem. Stress testing the coils will cost as much as replacing them, and you could still have another one fail in a month or two. Put 8 new ones in and you may get another 100K miles before you have this problem again.

 

[xford]

Yes, I would very strongly suggest that you replace all coils (COPs) and spark plugs (sorry). Make sure the plug gaps are correct (1.0mm). RFI noise from a marginal COP can cause false ETC codes. Your symptoms certainly sound like this could be the problem. Stress testing the coils will cost as much as replacing them, and you could still have another one fail in a month or two. Put 8 new ones in and you may get another 100K miles before you have this problem again.

Assumed that is what you would suggest as a first step and based on my mileage even it is not the COP's I should do them anyway. I was thinking about changing them out when I did the plugs but had not experienced any problems so figured why risk it. At the end of the day the plugs are not too expensive and the car has been very good to me. Another project on my hands and getting to that back valve cover bolt is a PIA. Thanks as always!

 

[LS4me]

Assumed that is what you would suggest as a first step and based on my mileage even it is not the COP's I should do them anyway. I was thinking about changing them out when I did the plugs but had not experienced any problems so figured why risk it. At the end of the day the plugs are not too expensive and the car has been very good to me. Another project on my hands and getting to that back valve cover bolt is a PIA. Thanks as always!

Been there, done that, have the T-shirt. Get a 7mm swivel socket (I got mine from Pelican Parts) and that bolt becomes no problem.

 

[xford]

Parts are in! Motorcraft COP's made in China :shifty:

 

[1LoudLS]

Parts are in! Motorcraft COP's made in China :shifty:

what isn't?

 

[joegr]

Made in China is not always bad (for the consumer). Ford should be holding them to some sort of quality standards, unlike the Chinese knock-off parts.

 

[xford]

Made in China is not always bad (for the consumer). Ford should be holding them to some sort of quality standards, unlike the Chinese knock-off parts.

I hope so - just got the project done (a little easier the second time - 1st time was just plugs) and she's running smooth - thanks for the input