Car hesitates and Raptor shift light acts like its restarting?

[justa03]

Alright guys im getting a little bit lost on this one. Got my car back together and still have a hesitation. Did a PPRV delete thinking that it could be it. When ever I get into the throttle and it usually seems to be right around 3k the car kinda falls on its face and the shift flashes like its restarting. After doing some research found out the wire that gets tapped for the shiftlight is VPWR for the PCM. That wire is actually fed by the bigger wire right next to it at the same connector. The main power comes from the BJB and then goes through the CCRM into fuse F2.2 in the CJB.

This might get a little bit confusing unless you have a good grasp on electronics. The wire that actually feeds VPWR to the tapped circuit for switched power for the shift light actually powers the coils. My question is could I have a bad coil that is back feeding power into this system causing the PCM to think it is being restarted VIA this and that the coil only acts up when under heavy load? I load tested the circuits and all of them pass, from there I ohmed out all the coils and all of them come out to be the same.

Im thinking of taking the coils out of my dads GT500 and putting them in my car and going for a cruise and see if this cures anything. Just looking for anyones input or if anyone has heard of or had a similar concern like this. Thanks in advance for any info or advice. :beer:

 

['03snkbt]

my thought is its a COP going bad since the shiftlight is tapped into it. mine has done this in the past and a new COP solved my issue.

 

[justa03]

How did you trace what COP it is? Man if that is it this will make my day big time!

 

[racebronco2]

If your car is not hesitating right after the shift or hesitating at 3000 rpms in the power band it is not the pprv. You should be getting a code for the cylinder that is miss firing. A bad coil does not have power to feedback into the system.

Does you odometer flatline or looks like this when it happens"--------". That is called flatlining, it means the ecu is failing to communicate with the vehicle. Mine did this sometimes, it was the sct 4 tune chip. Tried two of them and it always happened. The chip by itself was ok but i wanted more than one tune. I ended up buying an SCT handheld.

 

[46stang]

Could be a coil going bad. if it does it enough you should get a misfire for the cylinder that is misfiring or has the bad coil. If you have access to a good scan tool or know someone at a ford dealer you can pull up Mode 6 data which will show if you have a misfire on a particular cylinder before it sets a mil light.
Also i have seen a crank sensor do what you are talking about. It was on a 6 cylinder but on this particular car it would drop out consistently at 1600 rpms and the coils would shut off because of it. I put a new crank sensor in it and it fixed it.

 

[MTBSully]

Check simple things first. My shift light did the same thing when my negative battery cable was loose

 

[justa03]

Haha heres the sad thing guys I work at a Ford shop and have had my IDS hooked up to it multiple times. If you look at the schematic the wire that actually powers the ecu also powers the coils. I have seen it before where a coil actually backfeeds into the circuit and gives some really really funny things happening. So after watching the power balance many times and never setting a code I used the coils out of my dads GT500 and went for a quick test drove. Viola it ran like a champ, it slighty breaks up getting into it when it sees boost but the shiftlight never comes on and the car doesnt fall on its face. Now I believe it is just tuning to get it dialed in all the way. Not sure what coil it was but im just gonna replace all 8 with GT500 coils. Thanks for the advice on here guys appreciate it!

 

[46stang]

If you have an ids pull up the mode 6 data! The cylinder that has the bad coil will have the highest percentage just below the point of triggering a fault. You likely only have one bad coil and not 8. Are you the driveability tech? I was for 15 years, now I work for bmw. Anyways, glad you got it narrowed down.

 

[justa03]

Yea mode 6 was horrible man, checked that a few times. Problem was when it would break up/hesitate they all would just go haywire. That was one of the first things I checked. Youd be suprised how many guys never use mode 6 data. It was just a stupid thing but the way im looking at it with E85 and 21 psi on the kenne whose to say there isnt other coils on the way out? So just replace all 8 with GT500 coils, cheaper to buy all 8 from lethal then to buy one at a time at my cost which still comes close to $390, when lethal sells them for about $290.

 

[46stang]

Yea, that makes since.
Just an fyi, the other way I've diagnosed those was to disconnect one coil and injector at a time(the same cylinder). drive it or load it until it doesn't do it and then you know you have the right cylinder. For the age of the vehicle and the kind of power you're making, you're right, it probably is best to replace them all.