'97 Taurus Wagon GL, 147k: P0301 Misfire Cylinder 1

[Colt Hero]

Weird, but a day after replacing a ball joint and driving the car with a loose stabilizer link, my Check Engine Light suddenly started BLINKING (first time I'd ever seen that on ANY car I've ever owned). Thought for a minute that the computer could somehow tell that my suspension system wasn't completely intact, but the code turned up P0301: misfire cylinder 1.

First time I've ever seen this code on this car, but understandable since the plugs and wires are still original (I know, shame on me for not replacing them around 75k).

Ford says the replacements for this car are AWSF32PP's. $6.04 per plug. Wires are $55.56. Now normally I would just go to Autozone and buy Bosch or Champion or NKG replacements, but I've heard people say you should only put Motorcraft plugs into this car (Vulcan 3.0) because it's very finniky. People have experienced problems with other brands of plugs.

Any advice on changing the plugs on this car?

1.) Any special techniques or tools?
2.) Does a hotter engine make it any easier?
3.) Will I be able to get at the plugs facing the firewall? Will I have to rock the engine or partially dismantle it?
4.) Am I going to have a hard time getting the old plugs out since they've been in so long?
5.) What if an old plug breaks while unscrewing it?
5.) Should I just change WIRE #1 first to see if that solves the problem, then PLUG #1 if not?
4.) THIS CAR HAS ALWAYS SUFFERED FROM PRE-IGNITION (Pinging). ANY PARTICULAR

[Davescort97]

1. No special tools. Just a 3/8 ratchet with a short extension,universal joint and a 5/8 plug socket.
2. A hotter engine makes it harder. Let the engine cool. Aluminum heads can strip out when hot.
3. Try going in from underneath the car for those facing the firewall.
4. Shouldn't have any trouble if they've been in there for a while.
5. If the porcelain insulator breaks it won't affect your ability to get the plug out.
6. Replacing the wire and plug on the cylinder #1 first would be a good idea.
7. Preignition may have an affect on spark plug life.

[worthirt_99]

Originally Posted by Colt Hero

4.) THIS CAR HAS ALWAYS SUFFERED FROM PRE-IGNITION (Pinging). ANY PARTICULAR

I know gas is expensive, but if you're using regular gas, try moving up to special, it might make the pinging go away. I'm assuming that you've tried different gas stations.

[Colt Hero]

Replaced only the #1 spark plug wire this weekend and the P0301 code returned, as expected, within 3-5 miles of driving. So then I replaced the #1 spark plug and the code seems to have gone away. Only drove the car the same 3-5 miles, though, so who knows - the code may return tomorrow when I drive 50 miles roundtrip. Car drove a lot better than with just the wire replacement - no stumbling at all. Interestingly, other codes that I've been living with for two years also didn't reappear : 1131 (?), 430 (?), and 133. Not really sure on those code numbers offhand. They were "lean" codes and appeared to be related.

As for the old plug, it was dry, not oily or wet, and the curved "bar" that you bend to gap the plug was worn at somewhat of an angle. Instead of being a squared-off "bar", it was slivered or wedged toward one edge. The plug also appeared to be gapped a little too wide. It must've just worn to the point where the gap got too wide.

As far as doing the replacement, the plastic tray that the wire snaked through had to be opened, which meant some screws and nuts above needed to be removed first (no big deal). Then, a plastic standoff near #2 plug that held the #1 and #2 wires wouldn't unsnap for me (I ended up cracking it - oh, well). The immediate area around the #1 plug was amazingly clean - no need to blow any dirt out of there. Then, the plug came out very easily with a 5/8" socket and short extension (even though this plug had been in the engine for 10 years and 148k miles). The new one threaded in just as easily. Plenty of clearance to do this from the top. Although you really can't see exactly what you're doing, you certainly can feel the plug threading in with your bare hand.

I torqued the plug to 11 Ft lbs. This was within the range of what the Hayes book specified. As I always do, I cross-checked this number against the Ford shop manual, only to find an 80-117 (?) Ft lbs number. Another error in the shop manual - number in wrong column.

[shorod]

Originally Posted by Colt Hero

I torqued the plug to 11 Ft lbs. This was within the range of what the Hayes book specified. As I always do, I cross-checked this number against the Ford shop manual, only to find an 80-117 (?) Ft lbs number. Another error in the shop manual - number in wrong column.

Check that again. The units are lb-in in the factory shop manual. This converts to 6.67 to 9.75 ft-lbs.

-Rod

[UsedtobeSmart]

I have a 1997 with the Vulcan engine and I replaced my plugs and wires at about 135k with NKG's and got the cheapest I could find as well as the cheapest wire set I could find -- $25 delivered because I bought the stuff online through Parts America's website.

My car now has 137K on the clock and you wouldn't think it had more than 65K by driving it. Maybe I got lucky.

Yeah, if the plug was wearing unevenly and it overgapped itself like that you'd experience a misfire, alright. Should be running like a new car once you get all the plugs and wires replaced.

[Colt Hero]

shorod,

Just double-checked the Ford Manual and it's wrong. On page 03-07A-8 (last page of the 3.0L 2v section) there is a Torque Specification table. The fourth line down is Spark Plugs. The table has three columns: N-m, Lb-Ft, and Lb-in. For Spark Plugs it shows 9-20, 80-123, and "---" respectively for these three columns. The 80-123 should be in the third column, but it's in the second column.

Now interestingly, in the next section (4valve 3.0) the table is correct, but it's only a two column table with N-m and Lb-in shown. There's no Lb-Ft column, so the 80-177 appears in the correct Lb-in column there.

My Taurus has the 2valve engine. It's got the "U" in the VIN. The other indicator would be it's severe lack of power...

Usetobesmart:

I don't plan on changing any more wires or plugs right now. I've never done it this way before - I've always changed ALL the wires and ALL the plugs every time, but I'm going to take a different approach this time. Since the one plug came out very easily, I want to see how long each of the original plugs (and wires) will last (just for the fun of it).

[UsedtobeSmart]

Good luck with it -- it'll be interesting to see just how long platinum tipped plugs can last. I changed all of mine to get better fuel economy because, surprise, it was all OE. Really noticed more power with them in, too.

[Colt Hero]

Car started stumbling again (now at 158k) with the flashing SERVICE ENGINE SOON light, so I assumed it was the next plug failure (#2-#6) and I would finally get around to replacing the remaining plugs and wires. Pulled the code(s) to find that it was the #1 plug that failed AGAIN (P0301)!

Haven't touched anything yet, as the car is still driving reasonably well and I can't do anything until tomorrow at the earliest anyway. It stumbles after take-off at about the 2-mile mark for only a short while, then the SES light starts flashing, then it stabilizes (the light stays on because I've got lean codes I've been living with for two years or so ... 1131, 430, 133 - they're listed above, I believe).

So what do I do? The plug (Motorcraft OEM) and the wire (Autozone) on #1 were both installed new in October '07 (11k miles ago). Pull the plug and see what it looks like? Or put a (new) #2 wire on the #1 plug (it's still in the box) to eliminate the wire as an issue? Or can I somehow quickly prove it's the coil box (which is probably the easiest thing to work on since it's right out in the open)?

One other fairly new development. The car seems to be losing coolant. And there have been days where I've pulled into the driveway and gotten out of the car to go into the house and caught a whiff outside the car. Could this be related? Maybe the engine is running a little hotter than normal? I added two quarts of 50/50 coolant this morning into the degas bottle before leaving for work (which overfilled it to the HOT line, but if it's losing coolant, who cares - right?). I just did an intake manifold job on my Impala. Could I be headed for the same thing with the Taurus (or worse - a head gasket job??). I don't see any white smoke out the tailpipe and the temp gauge is ALWAYS midscale - it's ALWAYS in this spot. Makes me wonder if it's really measuring coolant temperature properly....

[shorod]

I'd pull the plug for #1 cylinder (even though it's not an easy one to get to) and see if it is exceptionally clean. If so, that could indicate that it's burning coolant.

-Rod

[Colt Hero]

OK, it took me a while to do it (I was busy "stress testing" my intake gasket job on my Impala), but I finally pulled the #1 plug. Turns out it looks fine - in the sense that the electrode is OK and the "arm" is OK. The only problem is with the color of the plug: it's sort of grayish-carbonized (but dry). No oil (except a little on the threads). It looked like I could've just cleaned and re-installed it, but I put a new plug in instead (one of the 5 remaining from the original set of 6 that I had bought).

So why is the #1 plug failing like this? The original plugs went 147k miles until the #1 plug failed (10 months ago). I replaced the #1 plug last October (10 months ago) and drove the car another 11k until the #1 plug failed again. The remaining 5 plugs are still the originals and seem to be fine (car is now at 159K+). Looking at those famous photos of various plug wear, it looks like the car might be running too rich (or lean ... can't remember which is was). I DO have lean codes all the time (1131, 133, and some 400-series code) - they've been around for at least two years now (in various combinations). Don't know why. One possibility is a vacuum leak, but I can't hear any. Another possibility is a bad O2 sensor (but which one .. both are original). I already cleaned the air filter cartridge ... (which was very clean and is also fairly new).

Am I going to be changing this plug every 10 months or so?