2003 plug and wire replacement

I'm a newbie and have never had a car this new - other vehicle is a 1991 F250-diesel. I just picked up this 2003 Crown Vic PI and it's getting a couple of codes.

Anyhow, i'm getting codes p0316 - misfire is first 1k revs, and p0305, cylinder 5 misfire detected. My research indicates that I should replace the drivers side plug that is closest to the radiator - and it appears to be under the air filter hose.

I've never done this before, so I'm hoping that I can get the following advice: Should I replace all the plugs at once, or should just replacing #5 be ok until i start getting codes again?

Are there any special tools I'll need?

I've heard that the ignition coil is in the spark plug wire, and that it could also be causing the code. How difficult is it to replace the spark plug wire thing.

There seem to be a whole lot of clamping things and air flow connectors that I don't want to mess up. Is there anything else I should do while it's disconnected like that?

Are there special plugs I should get or not get - are there special spark plug wires I should get or not get?

Is there a specific repair manual that you recommend for this car? e.g. chilton vs haynes or some other brand?

Thanks in advance for any thoughts you might have.

One good things is that at least I don't have to climb into the engine compartment to do anything like I have to in the truck!

Thanks!
David Knapp

All you need to do is to remove the air intake hose, remove the coil on plug assembly (7mm socket and extension and ratchet,) 5/8 plug socket, extension and ratchet. I would replace all 8 plugs or you will be replacing them one at a time until you replace all 8 and then start over again. The coil boots are more suspect than the coil to failure. Boot is around 8$, coil is considerably higher. They are easily replaced so take your time and enjoy doing the project yourself.

Is there any brand in particular for the plugs and wires that I should or should not use?

dbk

There are no wires. I am a firm believer in OEM tune up parts. Motorcraft plugs. The boots can be purchased at any auto parts store. You can price the boots at the dealer and parts houses to compare. You can also buy the plugs at parts houses. There is an emission sticker on the radiator support area that has the plug numbers on it.

I would check compression in the misfiring cylinder while the plug is out. Its also possible you have a bad injector. Use a spark tester and make sure you are getting spark. I also would use double platium plugs motorcraft. The price of parts today a little checking will save you big money over time. I'm sure way to old remembers when they were cheaper.

Update - yesterday the check engine light went off, and stayed off. I made about 4 trips yesterday and drove over 100 miles after it went off.

I was taught that problems with cars never fix themselves. My thought was that since the car is new to me, I should just replace the plugs anyhow, but I thought I'd ask about the possibilities of the car sitting for a couple months maybe caused a problem?

Also, it seems to me that the engine still isn't running at a fixed rpm during idle - is that normal or is that more likely the same or related issue?

Anyone have any preferred links for crown victoria repair manual purchases? I've been to 5 part places and none of them have the friggin manual.

Also, since it's a police model - is it worth getting the police manual that I see on ebay or is that pretty much a waste of money?

Thanks!
David Knapp

The check engine light went off because it did not detect the same problem in 2 drive cycles. I would still replace plugs to give you a base to start from on your repairs. Just purchase the manual for the CV. It will have all the information you will need. If the idle is fluctuating, look to the IAC motor or the MAF sensor. Both can be cleaned. Search the forum for MAF cleaning. There are some good posts and links to help you. The rewpair DVD's are good but you may need toi change the date on your computer to use it. Have fun and good luck.

one word of caution, don't be alarmed. when you replace the plugs, vacuum out the well they set in before removing the plug, and prior to inserting a new plug, AND use a torque wrench to tighten them to spec's.
why? they are aluminum heads, and there aren't many threads that hold the plug. if you don't get all the dirt out ( its a deep well the plugs sit in because of the head height ), or, if you don't tighten correctly, the plug will work its way loose, and when it gets near the top of the threads, the compression will spit it out, stripping the last couple of aluminum head threads. this is not un-common on 4.6L and tritons. its not rocket science, just keep the well clear of dirt, and tighten to spec's, using a torque wrench. if memory serves ( check me on this, my memory doesn't serve as well as it used to :), its INCH pounds, 120-180, which can be converted to foot pounds.

Hope this helps!!

1 inch pound force = 0.0833333333 foot pounds

http://www.onlineconversion.com/torque.htm (http://www.onlineconversion.com/torque.htm)
To convert foot pounds to inch pounds, multiply by 12.
To convert inch pounds to foot pounds, divide by 12.

When you put in your plugs buy some anti seeze and lube the threads. Also use this on any exhaust bolts or studs. Some people are breaking plugs because they didn't use this and the plugs corroded.

On aluminum heads let them cool down before trying to take out the plugs. If you don't they may strip.