Spark plug replacement

I have a 2003 crown vic P71 and it's at 120,000 km. I don't have the service records for the car, and I know that Ford reccomends changing the plugs at 100,000km. It looks like a big job. There is no cap and rotor, and there are no spark plug wires. Each sparkplug has a coil mounted overtop, and the fuel injector rail is right overtop of the coils.

Anyone know how big of a job it is? What's a ballpark figure for getting a shop do the work? I would do it myself if I knew that it won't take all day, and not damage other parts such as the injectors.

Thanks
Paul

Paul,

The service interval for the spark plugs is 100,000 MILES as far as I know, or just over 150,000km.

Replacing the plugs is EASY.

1) Using a vacuum or blow-gun, remove any dirt/sand from around the sparkplug boots.
2) Remove "zip tube" to access middle plugs on Driver's Side.

3) Using a 7mm wrench, remove the Coil retaining bolts (1 ea coil) and coils.

4) Disconnect the COP harness connectors (optional)

5) Using a 5/8" sparkplug socket and 6" extension loosen and remove plugs (if ANY sand etc. gets into the sparkplug well it may be very difficult to get the socket onto the plug flats. A small pick may be needed to loosen and remove debris).

6) Check gap on new plugs. If installing "Platinum" plugs, DO NOT alter the pre-set gap unless it is off by more than 0.004" from specs (0.052"-0.056").

7) Using a piece of rubber hose (~3/8" ID) slipped over plug insulator, install plugs finger tight into heads. Make SURE they do not cross thread.

8) Using a torque wrench, Tq plugs to spec. (13-15 ft-lbs). DO NOT OVERTORQUE or use ANY OIL or other lubricant (ie: neversieze) or you WILL overtorque the plugs.

9) Reinstall connectors, COP modules, and zip tube. Be sure to coat the exterior of the boots with dielectric grease, and to place a dab into the boots prior to installing.

You do not need to disturb the injectors or fuel rails. The COP modules will deflect enough so you can simply pull them out of the plug wells.

i have a 94 p71 and can like hesitation like when acclerating at low speeds be caused by old spark plugs? I heard i can be also be a dirty MAF sensor.

Yes, hesitation (not studdering) can be caused by a dirty (or bad) MAF sensor.

An article on cleaning: www.crownvic.net/tech/cleanmaf.html

Thanks ModMech :biggrin:

I went out and got the single pronged bosch platinum plugs to freshen up the motor. I think at the same time I will clean the MAF sensor. I'm gonna try to do the work this Saturday. The whole reason that I'm doing the tune up is because I'm getting awful fuel milage. 95% of my driving is on the highway and I baby it to try to get that extra fuel economy. I'm getting a lousy 20 miles to the gallon.

I have noticed a trend with my car as well. The fuel gauge almost instantly comes off the full mark after I fill it up. I mean that the gauge moves noticably off the full mark at 8 km, or around 5 miles. The gague also moves very quickly to the 3/4 mark. At the 3/4 full mark I'm lucky to get 90km or 56 miles.

I love my Crown Vic. The fuel milage really sucks!!! I am averaging 380km or 236 miles on 3/4 of a tank of fuel :shakehead

I'll post the results of my work.

Paul

Does the fuel you are using have ANY "oxygenate" in it (like ethanol etc), is it "re-formulated" for emissions?

I am using non-ethanol fuel blended fuel. In South Central Ontario the idea of ethanol blended fuels has not caught on. Aparrently it soon be manditory that all gasoline is sold as a blend of gas and ethanol.
I am using 87 octane fuel, which is considered regular.

I have only had the car for about a month, but since I have had it and been driving it I have put on about 2500 km. When I first got the car it averaged almost 22 mpg. I am struggeling to get 20 out of her lately. :disappoin

Paul