My 1999 Range Rover 4.6 has a little over 91,000 miles on it. I have been chipping away at Mike's recommended service over the past six weeks or so I have owned it. Since I purchased it I have only put premium fuel in it. Last Thursday morning I started my truck and was greeted with the Service Engine Soon light, after work I started my truck up and it started rather rough, almost like it wanted to die. After a liberal application of the throttle it was fine. The light stayed on and every time I start my truck it starts roughly, but does not run any differently on the road. Friday evening I went over to Autozone and had them read the codes and they were as follows:
P1884 (Transmission?)
P0340: Camshaft position sensor circuit malfunction
P0445: Evaporative emission control system purge control valve circuit shorted
P0102: Mass air flow circuit low input
P1669: Engine control module cooling fan circuit malfunction
P0134: O2 sensor circuit no activity detected (bank 1 sensor 1)
P0154: O2 sensor circuit no activity detected (bank 2 sensor 1)
P0135: O2 sensor heater circuit malfunction (bank 1 sensor 1)
P0155: O2 sensor heater circuit malfunction (bank 2 sensor 1)
P0141: O2 sensor heater circuit malfunction (bank 1 sensor 2)
P0161: O2 sensor heater circuit malfunction (bank 2 sensor 2)

I had Autozone clear the codes and the light came back on the second or third time I started my truck up afterwards, as well it still starts rough.
So all that being said, the next item on my to-do list is changing plugs and wires. Can I be somewhat optimistic that changing the plugs and wires might solve some of these issues? Anything else I should be looking at or doing?

I already purchased the plugs (Bosch Platinum +4) at Autozone, but they said they couldn't/wouldn't gap them, any tips on doing it myself or should I go back when the stoner kids aren't working?

Thanks.

 

Disregard the question about gapping the plugs, apparently you don't gap the +4's.

 

the bosch plugs are pre-gapped you are good 2 go with those. as for the codes did they all come on at once? after you had the codes cleared did you scan it again to see what came back? some of the items on the maitenance list can actually cause codes. Like sucking seafoam into the intake. Usually it's misfires. All of your codes seem to be related. I would start checking for leaks at the intake. did you recently change the air filter and forget to clamp everything? make sure the MAF is connected tightly and in the correct direction.

 

Well, I went out to get in my truck and go to work this morning and she wouldn't start. The lights come on, it clicks once, and I can hear a pump or motor running, but nothing else happens. All the clamps for the filter box are in their proper places and the MAF connections are fine. I had to rush to find a ride to work this morning so I did not get to examine the battery and it's connections.
Any advice on where to start once I get home from work? Searching through the site I've seen that it is relatively common for the crankshaft position sensor to fail in Discos. Would it be a fair assumption that it would go out in a Range Rover as well, especially given that one of the error codes was for a malfunction in that circuit?
I have plug wires on order from BP Utah, but my order confirmation only says to allow 5-7 days for shipping, so I am unsure when they will be in but I'm hoping they arrive soon so that I can get this issue cleared up and move on to the next one.
Between this truck and my ex-wife my monthly expenses certainly are increasing!
Thanks again for your help.