Fail-safe and Codes

2004LincolnLSV8

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So last weekend I was messing around with the LS and used a flexible intake tube to make a ram air style intake. (note...I have had an aftermarket air filter for a long time the only addition was the intake tube). After installation when I would drive for about 20 min the Engine Fail-safe would engage. I got engine codes P2104 and P2111. I figured since I did reset car (unhook battery) this was the issue. Even with a reset same issue would occur. I removed the intake tube to go back to the way it was with just my air filter and I "reset" the car again.

After resting the car it now runs fine with no Fail-safe unless I go WOT then the Fail-safe engages again until I turn car on and off. This time I get engine codes P2104 and P2112.

What could the issue be since everything is back the way it originally was...I am not able to go WOT without the Engine Fail-safe engaging...Thanks for any advice!!!
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Search. It's a common problem. Most likely, one (probably #4) of more of your COPs is marginal and causing noise that confuses the ETC system. If your 04 has less than 100K miles, Ford will stress test the coils and replace any failing ones at no charge to you. If you take it in, say that you are having misfires.
 
I have 5 out of the 8 coils replaced under warranty already which I thought was the issue too...could the COP go bad without any misfiring though??? My previous 5 COPs that went bad all made my car misfire but without ever going into Fail-safe.

I have not had #4,5, or 8 replaced yet according to my records.
 
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How did you determine that it is maybe #4?

#4 most often causes this problem, probably because it is closest to the PCM or some of the ECT wiring. I suspect that LS4me came to the #4 coil determination the same way I did. When this problem comes up, it is most often reported that #4 was the cause.
 
I have 5 out of the 8 coils replaced under warranty already which I thought was the issue too...could the COP go bad without any misfiring though??? My previous 6 COPs that went bad all made my car misfire but without ever going into Fail-safe.

I have not had #4,5, or 8 replaced yet according to my records.

It is very possible that the misfire at this point is too infrequent for you to detect.

Of course, it is possible (but unlikely) that your throttle body is actually defective.

So you've replaced six coils, but have three that were never replaced. Does that mean that one of the coils was replaced twice already?
 
It is very possible that the misfire at this point is too infrequent for you to detect.

Of course, it is possible (but unlikely) that your throttle body is actually defective.

So you've replaced six coils, but have three that were never replaced. Does that mean that one of the coils was replaced twice already?


Only five have been replaced....1,2,3,6,7
 
P2104 - Throttle Actuator Control (TAC) System - Forced Idle
P2112 - Throttle Actuator Control (TAC) System - Stuck Closed.
P2104 was set because the pcm had to step in to set the idle. The TAC system is in the failure mode effects management (FMEM) mode of forced idle. P2104 is just an informative code, set because of P2112. P2112 possible causes: Binding throttle body, stuck closed or
Damaged PCM

tell your dealer technician to follow pinpoint test DV1 in the workshop manual. (but also to reference test QE1) DV1 deals with him/her checking the throttle position voltages, if these voltages are not within spec, proceeding with checking for obstructions in the throttle body, then if this passes, he/she checks the wiring to the TAC assembly. there are many steps in this test and since the car isnt here i can't tell you where the test will go (throttle body assembly, PCM, etc.) most likely it will be the throttle position sensor which is a part of the throttle body assembly or a simple connector coming unplugged or wiring being cut, but once again since i dont have the car in front of me i can't be 100% sure. good luck. hope this helps.
 
^^ but as noted, electrical noise from a failing COP is a much more common cause for this code than an actual throttle body failure.
msgtuscmc, thanks for the info! it's good to help dealer techs along.

op, if you're in warranty, there's little to loose from getting the dealer to do the stress test. If all COPs pass, get them to run it again!
 
Only five have been replaced....1,2,3,6,7

Yes, but you said, "My previous 6 COPs that went bad all made my car misfire but without ever going into Fail-safe. " I assumed that if you had six bad COPs, you would have replaced at least six COPs.
 
Yes, but you said, "My previous 6 COPs that went bad all made my car misfire but without ever going into Fail-safe. " I assumed that if you had six bad COPs, you would have replaced at least six COPs.

yea my fault it was a mistype only 5 have been changed...I did make an appointment with the dealer Monday morning so hopefully they just swap out a COP or two under warranty...thanks for all the replies! :D
 
Went to the dealer earlier this week and they found no issues with the COPs and said that the CEL is from a failing throttle body (P2110 P2107). Since then I have been not going WOT so have not had any issues...is there another way to check if my throttle body is bad and not maybe some wiring or such??

I see some on throttle bodies on ebay for around $160 (used) but afraid to buy if this isn't really the issue.

Thanks!
 

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