Restricted performance when cold
 

Hi all, posting for a friend who has a 2005 S-Type V-6 with 110,000 KM. Recently the car started to display the dreaded Restricted Performance message after about 5 minutes of driving from cold. Pressing the reset button multiple times eventually clears the code, and then the car runs great for the rest of the day. I read the codes, and misfire on #5 cylinder was noted. Seems to me that a faulty Coil Pack is the most likely cause, but hoping that members here could advise - thanks in advance!

Tom

Attached is the cylinder numbering for the AJ-V6. Be sure the correct cylinder coil unit and spark plug are inspected.

Check for oil fouling of the coil unit as that can cause the coil to short creating misfire(s) condition. If there is oil in the spark plug wells the cam cover gasket and spark plug boss seals must be replaced.

i'm not aware of any reset button that could have such an effect.

I believe the OP is referring to the reset button on the DTC scanner device.

Quit using reset and instead fix the fault.

If talking about the reset button on the dash, perhaps the timing was just a coincidence. Several years ago when my '02 V6 was acting up in the same manner, the message (and restricted performance) would clear itself after a couple of minutes, with no action on my part. Had I been pushing the reset button on the dash the whole time, I'd have thought it was due to that.