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Engine Wiring Harness Replacements

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YellowBoss said:
I have done two engine harnesses also and even if the price of the aftermarket is expensive I also lost two days at Daytona because after the CEL the timing was locked. I don't travel as far but it was a waste of over a thousand dollars. You need to ask but to pull the cam sensors I believe you need to pull the engine and timing chain to get at them. Also yes the sensors do go bad, I was told by FR they don't normally go bad but have since been told differently by others. The factory wiring harness is cheap for these cars but takes about two hours to replace if you know what you are doing. The seem to hold up for about a year so the other option is to change it yearly with the plugs, slave, hubs, etc.
You have an early build too. I am probably going to just upgrade the harness versus waiting on the ticking time bomb knowing it will probably fail again next year.
 
Gary,

Put in a PRS harness and all those troubles are gone period. In three years I never saw one fail and I was looking for one believe me! It's a lot but once it's done it will never be an issue again.
 
mwilson7 said:
Gary,

Put in a PRS harness and all those troubles are gone period. In three years I never saw one fail and I was looking for one believe me! It's a lot but once it's done it will never be an issue again.
You convinced me! I'm gonna do it this winter and not worry about it going forward.
 
I forgot to mention that it can all be done with the engine in the car but the rear crank sensor takes some patience. Just keep trying....trust me. I've done it myself.......
 
mwilson7 said:
I forgot to mention that it can all be done with the engine in the car but the rear crank sensor takes some patience. Just keep trying....trust me. I've done it myself.......
Good deal. Fortunately the tech that pulled my engine last winter to install the headers said he'd come to my house and pull them. He had to pull it to do the O-ring TSB so he's had it out at least once already.
 

steveespo

Lord knows I'm a Voodoo Child
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I did the crank sensor in the car in 45 seconds. I do however have the urethane motor mounts that lower my engine 1/2". Also the cam sensors are accessible with the engine in the car. I also did my headers with the engine in, on my back in the driveway. And I am a fat bastid to boot!
Steve
 
steveespo said:
I did the crank sensor in the car in 45 seconds. I do however have the urethane motor mounts that lower my engine 1/2". Also the cam sensors are accessible with the engine in the car. I also did my headers with the engine in, on my back in the driveway. And I am a fat bastid to boot!
Steve
The difference between you and me is you have skillz Steve! ;-)
 
367
1
What is the O ring tsb :)
And is there a link to the PRS harness?

It's scaring me that a harness has become one of those annual items that needs replacing/checking on a car. If it ever comes to it, I'd also spring for the PRS variant.
 
boro92 said:
What is the O ring tsb :)
And is there a link to the PRS harness?

It's scaring me that a harness has become one of those annual items that needs replacing/checking on a car. If it ever comes to it, I'd also spring for the PRS variant.
The O-ring TSB is the crankshaft position sensor TSB to eliminate the random misfire issue (P030x)

For information on PRS see Boss_302's post #8
 
A friend came over last night and pulled the wiring harness and all 9 sensors. Man he's good; it only took an hour. Here's a shot of the right side cam actuators at the front with the head cover removed. I'm shipping them to Precision Race Services on Monday morning to be upgraded.



Uploaded with ImageShack.us
 
neema said:
A check engine light showing random misfires as well as specific misfires. Something made the car run rich enough to dump the cats out and decapitate the rear o2 sensors.


Not yet. It seems to be related to the engine running in open loop vs closed loop. The dealership says the o2 sensors are all fine, but it'll snap out of its bogged down misfiring mode and drove at 7/10 power before falling back into its lumpy misfire condition again. It's almost like someone unplugged a few coil packs.


I'll give the fuel filter a try

Neema: I had the same issues you are experiencing (P0300 & P030x misfires followed by cat failure codes - P0420 & P0430 if I recall). I would get the misfire codes almost every track session then on the drive home would get the cat failure codes. The P0300 $ P030x codes are a common problem that have been thouroughly covered on this forum but I don't recall anyone other than you and I having the problem in conjunction with cat failures.

The long and short of it is that my dealer tried many things that didn't fix the problem, but once the TSB for the Crank Position Sensor O-ring was performed I haven't had a single misfire or cat problem. I went from exiencing the problems every track day (about 20) to no issues since the TSB preformed (about 10 track days). Get your dealer to do the TSB for the O-ring and you won't look back.
 
KBBOSS1086 said:
Neema: I had the same issues you are experiencing (P0300 & P030x misfires followed by cat failure codes - P0420 & P0430 if I recall). I would get the misfire codes almost every track session then on the drive home would get the cat failure codes. The P0300 $ P030x codes are a common problem that have been thouroughly covered on this forum but I don't recall anyone other than you and I having the problem in conjunction with cat failures.

The long and short of it is that my dealer tried many things that didn't fix the problem, but once the TSB for the Crank Position Sensor O-ring was performed I haven't had a single misfire or cat problem. I went from exiencing the problems every track day (about 20) to no issues since the TSB preformed (about 10 track days). Get your dealer to do the TSB for the O-ring and you won't look back.
+1 on the O-ring crank sensor TSB solving the P030x misfire codes.
 
KBBOSS1086 said:
Neema: I had the same issues you are experiencing (P0300 & P030x misfires followed by cat failure codes - P0420 & P0430 if I recall). I would get the misfire codes almost every track session then on the drive home would get the cat failure codes. The P0300 $ P030x codes are a common problem that have been thouroughly covered on this forum but I don't recall anyone other than you and I having the problem in conjunction with cat failures.

The long and short of it is that my dealer tried many things that didn't fix the problem, but once the TSB for the Crank Position Sensor O-ring was performed I haven't had a single misfire or cat problem. I went from exiencing the problems every track day (about 20) to no issues since the TSB preformed (about 10 track days). Get your dealer to do the TSB for the O-ring and you won't look back.

cloud9 said:
+1 on the O-ring crank sensor TSB solving the P030x misfire codes.

Thanks for the replies guys. My dealer is trying a new PCM. I'm a skeptic, but I guess it can't hurt. I'll suggest the o-ring TSB or do it myself.


this forum is awesome
 
neema said:
Thanks for the replies guys. My dealer is trying a new PCM. I'm a skeptic, but I guess it can't hurt. I'll suggest the o-ring TSB or do it myself.


this forum is awesome
Make your dealer do the O-ring TSB because you need to have them perform the "neutral profile relearn". I'm not exactly sure what that does, but I'm assuming it sets a "0" position for the crank sensor. Getting the crank sensor out isn't bad but the relearn needs to be done with the dealer's calibration equipment.
 
cloud9 said:
Make your dealer do the O-ring TSB because you need to have them perform the "neutral profile relearn". I'm not exactly sure what that does, but I'm assuming it sets a "0" position for the crank sensor. Getting the crank sensor out isn't bad but the relearn needs to be done with the dealer's calibration equipment.

Will do. Thanks for the help
 
neema said:
Will do. Thanks for the help

I had the misfire codes coming up after the first 1000 miles (no limp mode) every 200 or so miles in regular street use (no racing) and the O-ring TSB solved them for my 2013 Boss. No issues in more than 7000 miles since the O-ring TSB was done.
 

ArizonaBOSS

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cloud9 said:
Make your dealer do the O-ring TSB because you need to have them perform the "neutral profile relearn". I'm not exactly sure what that does, but I'm assuming it sets a "0" position for the crank sensor. Getting the crank sensor out isn't bad but the relearn needs to be done with the dealer's calibration equipment.

The Misfire Monitor NP Relearn gives the engine a baseline of knock data to expect at idle and working RPMs (4000, IIRC) so it can then determine what is "abnormal" based on that criteria.
 
About to order the race engine harness from Rehagen just for peace of mind.
Will do the O-ring on the crank sensor but can't find a dealer able to perform the relearn procedure...(outside US).
I guess I am stuck with that.
Anybody changed the o-ring (before having any issues DTCs / CELs / etc...) without performing the relearn?
Thx.
 
patrickshelby said:
About to order the race engine harness from Rehagen just for peace of mind.
Will do the O-ring on the crank sensor but can't find a dealer able to perform the relearn procedure...(outside US).
I guess I am stuck with that.
Anybody changed the o-ring (before having any issues DTCs / CELs / etc...) without performing the relearn?
Thx.
Maybe indy (non-dealer) tuners can do it remotely or with an email tune? Shaun @ AED? I am not sure what is included in the relearn exactly but it is practically a tuning procedure if I understand it correctly. Maybe in this case a simple reloading the factory tune would do the trick? I would send an email to Shaun at AED http://www.advancedenginedevelopment.com/company-overview
Just a thought.
 

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