98 Grand Marquis Mis Firing

My 98 Grand Marquis is miss- firing. I got a check engine light. I will bring the car in for service tommorow, but I am told that this is an expensive ordeal The spark plug colis fail and they are $60/each The spark plugs have alreay been replaced. nyone else have a similar probelm? The car has 125,000 miles on it M

Reply to
mstrspy
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REPLACE THEM ALL!!! I did mine and it was the best thing I did to the car, it now runs like new. You can try replacing the boots only along with the plugs and see if it helps. (don't forget the lube)

Reply to
chuckster

Replacing them all sounds like the right idea. I don't want to keep taking time off from work and going to my mechanic to replace these things one at a time. Anyway, may I ask roughly what the replacement cost off 8 coils was for you? I'm guessing it is about $400.00 for parts for all 8 coils

Reply to
mstrspy

Did they replace the plug wires? Wires can be a major cause of mis-fire on 4.6's from the 90's.

I got about 6 yrs/40k mi. on my 4.6 before I had to replace the wires.

Cheers, Puddin'

Reply to
Puddin' Man

I purchased all 8 coil packs from Auto Zone for about $65.00 each, I guess I got ripped off as Toms post said they go for $35 aftermarket. (give up your supplier Tom!) I am happy and everything works well after

35 K miles. A small investment for a pain in the ass problem, I say go for it along with a set of quailty plugs. Job takes less than 60 minutes and that way you will know what you have when you are done. (don't forget the lube!)
Reply to
chuckster

well, if you insist. ;-)

Napa online. that was about 18 months ago. I can't see them going up that mush though.

Reply to
tom

A LOT of parts have doubled in price over the last 18 months. Since NAPA took over completely from UAP here in Canada the prices have gone up and the quality of parts has taken a dive. Prices at the dealeships have also, in many cases, gone absolutely NUTS.

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Reply to
clare at snyder.on.ca

I just checked out my super secret parts supplier and found out they are $50 each. Here is the source:

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I went to Auto Zone because they had them in stock and a young girl with big hooters waited on me and I lost all financial control and could not help myself from over paying, Hell, I used to stop in just in to buy one quart of motor oil at a time instead of 5 quarts at one time, just to look at her. She has since left my local Auto Zone, so I just go for the best price online for parts and buy my oil at Wal Mart, and save big. (don't forget the lube!)

Reply to
chuckster

I'm the original poster. I will get this fixed tommorow. My brother is my mechanic and owns his own repair shop. I will find out the bottom line cost for these coils. too bad they are so expensive. eems like a crappy design. I do know that they almost always fail.

Reply to
mstrspy

My newest vehicle is a 98 Explorer - still the older 'distributorless' ignition system. When the ignition wires failed for the second time, I thought that COPs were the ultimate solution to this problem. What's better than making the high voltage right on the plug? No long path with twists and turns, no insulation to dry out, no cross-firing between cylinders when you don't dress those wires properly, even less opportunity for radio frequency interference... But from reading the adventures of those who actually own those things, I understand that instead of replacing a set of wires every couple years for $100, now it's a set of COPs for $500 (dealer's prices). Assuming that you even know how to diagnose those things -- is there a spot to stick a scope probe in there at all? Does this 'improvement' make any sense?

Reply to
Happy Traveler

Better the reason to not ignore maintenance on the ignition system.

Not "in" there. -On there.- COP secondary scope pick up is placed on the coil, much the same as was done for the old GM, Honda, Toyota coil in cap designs. Primary is accessed the same as always unless the coil driver is integral to the coil, primary 'mirrors' secondary so useful except for absolute exact KV values. Primary current waveform is also available off of the primary lead.

From a service standpoint, probably not. From an emissions and driveability standpoint, probably yes.

Ford claims that a very high percentage of COP coils replaced under warranty are not defective...

My experience has been that there are more problems with carbon tracked secondary boots and more problems with the terminals that connect the primary.

Reply to
Neil Nelson

Paid $90.00 installed for one coil. I got the part at cost for $70 and paid my brother $20.00 for installation. What a huge rippoff these parts are. Someone mentioned they got theirs for $35? Where? My brother owns his own garage and I saw what his exact cost was.

Reply to
mstrspy

You have the benefit of your brothers knowledge that there are superior and inferior parts being marketed.

Reply to
Neil Nelson

Reply to
mstrspy

Well, How does it run after the coil replacement?? Problem solved?? So I guess I didn't get ripped off at $65 per coil. I am happy today. Life is good.

Reply to
chuckster

The car runs good now. No more skipping. I did take the old part with me because I wanted to test it to see why it failed.

This coil assembly c>Well, How does it run after the coil replacement?? Problem solved?? So

Reply to
mstrspy

Yes you can buy just the "boot-wire" seperate. Like I said in a previous post this is a cheap fix if you want to replace the boots only, I did not not want to mess around with the trial and error of finding what coil was bad or wire insulator going bad. I suggest replacing every wire-boot when you change the plugs, on these COPS.

Reply to
chuckster

Reply to
mstrspy

Wires/Boots are about $6 each. (Don't forget plugs and lube) BIG TIP - blow out the clyinder head area with air PRIOR to removing the plugs.

Reply to
chuckster

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