99 Explorer Sport. My spark plugs keep getting fouled up.

[jhiavila]

Hello, i have 1999 Ford Explorer Sport with 130,00 miles. About 3 years ago i took it in and had a full tune up done on it (spark plugs/wires,O2 sensor,fuel filter, belts) because the engine was rough during idoling and seemed to be misfiring, and a sulfer odor coming out of the exaust. Problem solved truck ran fine. About a year ago the same simtoms began to reappear. This time i took it into a family friend who replaced the fuel filter, spark plugs and wires. Again problem solved truck ran fine. Now a year later im getting the same issues. I replaced the coil myself thinking that could be the problem but it hasnt helped. Should i replace the plugs and wires again, or does it seem to another issue considering i have replaced them twice over the last 3 years and only put about 10,000 on the vehicle over those 3 years.

 

[BrianDye]

It shouldnt be your plugs or wires....they should last way longer than a year...

 

[jhiavila]

any other possibilities? replacing the wires and plugs has helped in the past though, but i agree they should last longer then a year

 

[Mark98]

Sounds like something is fouling/ruining your plugs (hence only lasting a year.) Is the check engine light on? Almost sounds like it's not getting the correct fuel to air ratio.

 

[BrianDye]

Sounds like something is fouling/ruining your plugs (hence only lasting a year.) Is the check engine light on? Almost sounds like it's not getting the correct fuel to air ratio.

I mean to ask that too, when you change your plugs, do they look real bad?

 

[Sams01XplrSprt]

welcome

 

[jhiavila]

Yes, a few of them had a lot of corrosion on them. Any idea what the strong sulfer smell is. Smells like when someone lights up a match.

 

[Sams01XplrSprt]

i remember a long long time ago my explorer exhaust had a bad sulfer smell to it smelled like rotten eggs i dunno what caused the smell.

 

[BrooklynBay]

Welcome to this forum! I've renamed, and moved your thread to the stock 95-01 section. Post a picture of one of your plugs.

 

[eXcali]

If you put cheapo plugs and wires in they could go bad in 1 year. The motorcraft are the ford Stock plugs, always use those if they are available. Most places only charge about $2 per on them as well. They are also rated for 100k. As for the corrosion on them, if they are the wrong temperature plugs this could contribute to this buildup.

 

[Explorerdog]

Hello, i have 1999 Ford Explorer Sport with 130,00 miles. About 3 years ago i took it in and had a full tune up done on it (spark plugs/wires,O2 sensor,fuel filter, belts) because the engine was rough during idoling and seemed to be misfiring, and a sulfer odor coming out of the exaust. Problem solved truck ran fine. About a year ago the same simtoms began to reappear. This time i took it into a family friend who replaced the fuel filter, spark plugs and wires. Again problem solved truck ran fine. Now a year later im getting the same issues. I replaced the coil myself thinking that could be the problem but it hasnt helped. Should i replace the plugs and wires again, or does it seem to another issue considering i have replaced them twice over the last 3 years and only put about 10,000 on the vehicle over those 3 years.

I know this has been a long time now for you but mine was narrowed down to one particular plug with a code as I suspect yours was one plug not all them. So now I get the symptoms (basically it chokes) I keep replacing the #3 spark plug and it keeps fixing the problem. Mine possibly has a crack in the head or..

 

[masospaghetti]

What type of plug did you use? These vehicles use a waste-spark system that fires the spark plug twice as often as a traditional system. In addition, the polarity reverses each time, so the anode and cathode switch back and forth.

Read about it more here, described better than I could: http://www.aa1car.com/library/sparkplugs_for_dis.htm

From the site:
Though many technicians and do-it-yourselfers believe that copper core plugs can be used on waste spark DIS ignition systems, Autolite says that is not true. Ordinary copper spark plugs may function well initially, but the electrodes will wear prematurely and eventually cause ignition misfire.

Unlike conventional ignition systems, waste spark DIS ignition systems use half the spark to fire the opposite spark plug unconventionally from the side electrode to the center electrode. Copper core standard plugs and copper core single platinum spark plugs are not designed to withstand this reverse polarity firing and will suffer premature gap growth due to center electrode erosion. Gap growth will stress ignition system components by requiring more voltage to fire, eventually leading to misfire, loss of performance and fuel economy. This degradation can be noticeable as soon as 20,000 miles after the plug is installed.

EDIT: My 98 XLT has a problem with one plug getting fouled every six months or so. I think that cylinder is burning oil from bad rings or valve stem seals. If this is the case, you can try using a "hotter" plug that will resist fouling better than a standard one, with an increased risk of engine knock or pre-ignition.