As you know from my most recent post I all of a sudden on Friday night got a bunch of misfires and all the codes of p0303 and 1313 and 1316- .../.

It has smoothed out and I get the pending same codes if I try and push.

I an almost 99% sure this has to be the coil on 3 that had replaced with a new Jag one on Jully11 ( covered under warranty)

This may be an incredibly silly question, but here goes. I had to get a new aftermarket cat and it was welded in. Is there any chance that any part of the weld failed that would somehow cause only a misfire on #3?

Is is also common to have a major misfire starting at idle and then on light acceleration that would somehow smooth out and only occur when you stomp on it. Why would not the coil stay in the original failure mode?? This is the one area that makes no sense to me.

Is there any other reasonable item that could cause a misfire on only one cylinder other than the coil. I have no other codes that point to anything but the DTC of p0303.
Just trying to cover all bases before I take t back to the mechanic as I know some try to blame other items that what they are responsible for.

Thanks

Tom in Dallas
2005 S0Type 3.0 76500

 

Any wiring involved???

 

Tom, check the fuel injector connector to Cyl #3 - ensure that connector is tight and snug on the injector.

 

Interesting and thanks- would that cause an intermittent problem with codes 0303 and 1316. Today I drove the car - no problem. Made a stop and started out of a parking place at 10 mph and felt the tug. That went on for about 1/2 a mile and then it disappeared. Went to freeway and up a hill red-lined the car up to 100 mph, then stepped off the gas and the tug/misfire started again- then settled down after 2 miles of straight 70 mph. Stepped on it again and nothing- then again and the misfire- also hear a sound sometimes between shifting (automatic) from second to third that sound like a quick single cylinder detonation, but no flashing CEL and no codes but the above 2. Then that will disappear.

Had all plugs and coil #3 and #5 replaced on July 11- new cat July 12.

Would I not smell gas in the situation you describe and would it act so intermittent?

How would I even check the fuel injector connector? Would that not generate a different code and would it all of a sudden happen after 3 weeks??

Thanks

Tom in Dallas

 

Not sure- but sounds like you are suggesting that the wiring from the ecm to the coil on #3 might show an open proble. It may, but nothing I did and it has run perfectly from July 12 until Aug 1 and this just happened all of a sudden on a restart of the car.

I have no way to swap the coil, since it is #3

Thanks

Tom in Dallas