I just bought a 2002 jaguar xk8 and sometimes when I get in it will not turn over or start and I'll get a few messages saying: engine failsafe mode, gearbox fault, traction control fault, and asc fault. Sometimes it will happen while I'm driving. When this happens I can wait a couple minutes and it will crank right up. The engine does not miss but is a bit sluggish when it does run. The transmission shifts a little rough sometimes. I just put a battery in it, so it shouldn't be that. The tps sensor looks new but I did not replace it. There is a code for an O2 sensor on bank 2 (p1647). I've got codes for the input turbine shaft (p0715) and CAN tcm to ecm malfunction (p1797). This is all the info I have right now

 

I dont care if its a new battery ..charge it overnight ..clear the codes and start again

 

[QUOTE=Pistnbroke;2683947]I dont care if its a new battery ..charge it overnight ..clear the codes and start again]. I tested the battery and it came back perfect, 100% charge. I also cleared the codes and it did fine for a little bit but It went into reduced power mode while I was driving but went away after about a minute

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The only reduced performance I have had is when it has got water into one of the spark plug holes via poor seals on the coil covers.

 

i just replaced the valve cover gaskets, plug well gaskets, plugs, and coils last week. They are all holding fine

 

Did you fix the bad O2 sensor?

 

I have the new sensor, I'm just trying to get a socket to get it out.