Coyote Surging and stalling

[Sunny66]

Have about 100 miles on my new Cobra, which has the new Coyote 5.0 with a tune. Noticing two issues:
1) The car surges and bucks with the slightest (and I mean SLIGHTEST) lift off of the throttle. Makes driving around town and parking really hairy!

2) When coming to a stop or a low speed turn and pressing the clutch, the RPMs occasionally drops so low that it stalls. Not good when going into a turn!

Anyone have any ideas as to what's going on and possible fixes?

[fordracing65]

Check your IAC, the IAC allows a little air into the engine when the throttle blade is closed. The PCM meters the air via the IAC valve and the behavior mimics the dashpot on a carbed engine. If the IAC is dirty or faulty then in cannot deliver the correct amount of air when it is suppose to and the engine will die. If all else fails drill a small hole or a few small holes in your throttle blade to help aid in some air flow when the throttle blade is closing, it will trick your computer and not die...

[Wbulk]

About six months ago I was reading everything I could on the Coyote engine potentially for my next project. The symtoms you describe sound very familar to problems they had when they first came out with the engine for the hot rod market in 2011. There was a solution for it but I don't remember where I read it. I seem to remember needing a vehicle speed senor that went in the bell housing or trans, but I am not really sure. You might try the FFR forum, they have threads just for the Coyote.

[MJJ]

Originally Posted by Sunny66

Have about 100 miles on my new Cobra, which has the new Coyote 5.0 with a tune. Noticing two issues:
1) The car surges and bucks with the slightest (and I mean SLIGHTEST) lift off of the throttle. Makes driving around town and parking really hairy!

2) When coming to a stop or a low speed turn and pressing the clutch, the RPMs occasionally drops so low that it stalls. Not good when going into a turn!

Anyone have any ideas as to what's going on and possible fixes?

Who tuned your engine? What CAI are you running? Make sure you have a tight connection with your cai as well.

[PSB]

Here's the device Ford made to fix the well known Coyote stalling issues: http://www.summitracing.com/parts/fms-m4209adptac

Of course, FRPP never admitted there was an issue, so the device is for "Speedometer Recalibration"

Pete

[Cashburn]

Ask your dealer if they installed the Speed Dial that was linked above. Beyond that it sounds like an improper tune. You mentioned a Jon Lund cam tune in a previous post, that requires a dyno adjustment to function and also compromises drive ability.

[Cashburn]

Originally Posted by PSB

Here's the device Ford made to fix the well known Coyote stalling issues: http://www.summitracing.com/parts/fms-m4209adptac

Of course, FRPP never admitted there was an issue, so the device is for "Speedometer Recalibration"

Pete

That's what it was actually for when they released the original around 1996. It was to allow gear swaps when your speedometer no longer relied on a mechanical gear drive off the transmission.

It has a new purpose given the Coyote setup.

[diverrick]

And what purpose would that be? Just want to know, not wanting to be a troublemaker, but I am learning too.

[Cashburn]

Your installer may also have the polarity wrong on the Speed Dial install.

Here's a brief overview: • View topic - 5.0L COYOTE ENGINE SPEED DIAL INSTALLATION

[jualwatt]

I can vouch for this "fix" working. Vintage Motorsports just installed this unit in my Backdraft with a Coyote Aluminator and the stalling issue and some gunshot intense backfiring on decel is now a thing of the past.

Julian