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Failsafe Mode

3456 Views 10 Replies 4 Participants Last post by  kj_cinci
Whats up fellas I recently bought an '05 Mustang GT. I've had it for about 7 months with the C&L cold air intake & predator tuner. About three weeks ago I was at a red light and when the light turned green as I released the clutch the car went into an engine fail safe mode which cuts your power in half. All my gauges were normal. I drove it to the dealer and when they turned it on it was back to normal. I had been driving it like that since then and the car did the same thing on Monday again I just turned it off and then on again and everything was back to normal. It is at the dealer now but they're telling me that if the warning is not on the diagnostic tools will not detect anything. By the way I noticed that lately as I release the clutch theres been a vibration that I feel on the rear wheels almost as if the clutch is not fully engaged. Sorry for the long letter but I need HELP!!!!!!!!!!!!! Has anybody else come across this problem?:worship
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Hi and welcome to our site! :)

Sorry it took the dreaded 'Limp Home Mode' to bring you here... BTW you have nothing to worry about!

It has to do with your CAI and tune/-r. Ford will probably not be able to help you if they don't tune cars? I had this happend to me and it was the torque limitor... Do a search on here (under limp home mode or fale safe mode, think I posted under engine fail safe mode...)

In short, your computer senses something is wrong. It might be the air / fuel but more likely the TQ limitor. I had my tune corrected to alow for more TQ on the drivetrain... It was allready moved but not enough, also under hard driving remember to turn off the TCS as that's what sent the error code in my case...

You'll coul see a professional tuner to have this corrected. The best would be if you could go there with the error code up... also get a better tune at the same time! :happyhapp Or, C&L/Predator should have a file for the fix now... call C&L and/or where you bought it from and they should be able to e-mail you the fix, or even download it from C&L or Predators websites...

Ken at took care of mine but he's mostly an SCT guy... maybe a good time to get a better tuner (both the part and the guy! :rolleyes: )
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Big sigh of relief

:laughlitt Thanks KJ for answering my question and I'm sorry I joined your site because of my situation but I'm here to stay. I browsed around yesterday for about 3 hours and I didn't want to leave. What a great site I mean were else are you going to find so many pony enthusiast in one place. Again thanks for your advice. By the way I'm getting a Steeda underdrive pulley and bessani X pipe for X-mas so I can't wait to feel the results. Later:eyepoppin
No worries! And we're glad to have you!

Those are good additions! I would myself have gone another route and gotten headers with the X... a bit more pricey but I think a better investment! See the thread Headers Install! AFM members have a special on the Kooks system!
Would the limp home mode be triggered off of normal acceleration because that's the way mine was triggered?
is limp mode like a northstar wher it quits firing every other rev so it can run undamaged without coolant? kinda wondering if so:
weak motor mount might be pulling on wire harness at take off- like maybe a coolant sensor plug?
I just had to replace one of those 'hydromounts' on my wifes windstar- putting in drive was making engine jump so hard it was tearing up exhaust symptoms, just noticed when looking for a unrelated noise in the suspension. apparently something broke inside the mount- top bolt was a PITA to remove as it was spinning inside the mount- old mount would flex about 3/4 inch, replacement maybe 1/ visible cracks or anything...just wondering...
First time it happened for me was during normal acceleration but over some sand laying on the road, anti spin kicked in and then it gripped on the clean asfalt...

It moves the rev limitor to the high 3000's or maybe 4000. CC doesn't work, AC is downgraded... it is so you can get of the road, maybe even to Ford for a serious prob, like a cooling issue. In most cases I've seen here it's come up to protect the engine/drivetrain through the air/fuel inputs in poorly or un tuned modded cars, or the TQ limitor on modded cars... The stock computer cannot understand the extra air with a CAIed car, give a CEL or in worse cases the Fail Safe Mode...

It is a PITA to drive with and it will reverse itself if you shut the car down and restart it, unless something serious is going on I'd guess...
I am currently experiencing a nasty encounter with Fail Safe as well. I installed the C&L CAI with Predator tune about 3 weeks ago without any problems. Immediately noticed the improved throttle response like everybody else has but was disappointed that I would still randomly get the throttle surge and\or hesitation problem some have reported here as well. One thing to note, on one thread somebody mentioned how they "calibrated" the throttle by having the key on, engine not started, and slowly depressed the accelerator to the floor for about a second duration. I only did it once, but I never encountered the surging problem again. Ok, off topic a bit, but here's the "rest of the story".

Last Friday, with no prior symptoms displayed, I jumped in the car to run an errand and could hardly get it started. After repeated try's I was finally able to, but in Fail Safe Mode. I turned it off, waited, restarted, same result. This was done more than once. The smell of gas was very strong and black smoke to boot.

Plugging in the Predator and going to the Dianostics mode, it indicated one Unknown error and two errors for the O2 status sensor "locked, burning rich", both banks. Thinking I may have a system glitch or stuck bit, I reflashed the computer with the performance tune. No change. I then disconnected the negative cable for the battery for about 30 minutes; reconnected, attempted to start, still no change. Lastly, I pulled off the C&L, reinstalled the factory air box, restored the original Ford program...NO CHANGE! Didn't know what else I could do at this point, so brought it to the dealership this AM on the back of a tow truck. Let me tell you, nobody wants to see the joy of their life on the back of a tow truck! It killed me!

Haven't heard from the dealership yet, but have a pretty good relationship with them so hopefully they will get it figured out ASAP.

Btw, I bought my 5 speed GT on December 3, 2004. I now have over 39K miles on it. The only other mods I have done to it are FRPP Strut tower brace and coil springs, and Saleen short throw adapter.

Anybody else out there have a similar experience?
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I've seen this on a blown car, where it was running rich, clogged the cat up and actually grenaded the engine!

Whatever you do do NOT mention a CAI or AM tune!

Good luck! Keep us posted!
Ok, 12 days later Ford finally got my car started, after replacing the PCM, the second time. Apparently it took a few days to get one in and when they did, it still didn't work. Fortunately it was a little easier to get a second one and it did work. They also replaced the plugs. I should have it back tomorrow afternoon for the weekend!!

Hopefully I'll get more details tomorrow about their troubleshooting and parts replaced.
I hope it is PERFECT now! I can only imagine not having her... =(

(She's actually going under the knife next week, new motor, blower, etc... oh well, she'll be like new when she recovers!)
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