Hi,

I just consulted my manual on when it is advised to change the plugs, but as always, I wanted to consult with the experts on this board. When is it generally advisable to change the plugs? Also, should I use stock plugs, or i sthere a beneficial (BUT SAFE!) alternative?

Thanks!
Chris

 

I am in the same boat, I bought my 97 used. It has 65 k on it. The truck was a lease return and I am pretty sure the plugs have never been changed.

I am going to be under the hood this weekend changing the water pump (it is leaking) and I thought I might as well change the plugs also.

 

Stock plugs are fine. As far as when to change them, the opinions vary there. For the $8 it cost to do the stock plugs. I'd do it at the miles you are just as good PM.

I have personally removed plugs from the Ford engines with over 100K on the plugs. The engine still ran fine and the plugs had little more than nubs left for electrodes. The ignition system made up for the worn plugs. However the mileage and performance were definitely improved after they got changed.

 

Ok I replaced my plugs went with Bosch copper, the place had stopped carrying motorcraft, which I thought was strange.

I found that one of my plugs was broke, the end was snapped off in the boot of the wire. So all this time I was only running on 5 cylinders. I never even noticed it. I found that strange.

 

Not that hard to believe. Considering that the ignition system is capabale of a hell of a spark it could jump that gap fairly easily.

I mean yes you'd think you'd notice it but it doesn't surprise me it made the spark jump that gap. The only downside is that it puts the coil pack under a lot of load for an extended period of time. They unfortunately don't come as sepereate coil units. They are a single unit for all cylinders. At any rate as long she runs good I'd say you got a lot better situation on your hands now.

I have measured a (and I'm not kidding) .250 gap on plugs that were still firing after 125K miles.

That is 1/4 of an inch. That is a HUGE gap in the world of ignition systems.

 

Might even help my gas mileage also. So what are your feelings on the Bosch plugs.

 

I think you'll notice an immediate improvement in mileage and performance.

As to the Bosch plugs. I have heard of complaints of poor performance...missing...intermittant things. Others have said there has been no problems at all. So I can't say one way or the other except to say that if something starts running wierd soon after that would be my fist place to look.

 

As to the spark plug question, I like the Motorcraft Platinums but that is just my opinion. Bosch also has a good reputation in many applications. I tend to chage my plugs at about every 45k and the gaps are usually out of spec by then. My wires needed changing at about 70k. They were not the most durable so baby them when removing the boots. A new set of Ford wires runs about $40 I think. Remember, the heads are aluminum so be careful when putting the new plugs in-you may want to use a torque wrench if you're really feeling really **** that day.

 

What is the torque for spark plugs.

 

The shop manual says something like 80 to 183 in-lbs, so I was going to use around 130-140 in-lbs.

 

I asked for plugs today at Autozone and they didn't stock the Motorcraft plugs. Advance didn't have Motorcraft Platinum so I got the Autolight Platinum. Always thought Autolight and Motorcraft were the same. Guess tomorrow I get to find out if any of these plugs are hard to get to. Every vehicle I've ever owned had one plug that was nearly impossible to get to and required some trick.....

 

I use a two foot extension, and a universal, and go throug the wheel well....I use Bosch Platinum+ 2. They haven't given me any problems since I put them in. I had problems with Autolites - kept getting a miss.....

Robbie

 

Remember to use some sort of anti seize on the plug threads and dielectric lube inside the plug boots!!!!

 

Changed mine Thursday night. The biggest grip was getting the plug wires off the plugs. I though I was going to pull them suckers apart. The clung onto the plugs pretty good. Once I got the wires off the plugs it was simple. Surprisingly none of the plugs were too difficult to get too with a 6inch extension.

It had Motorcraft Platinums on there and they were eat up pretty far out of specs. I'd imagine they had been in for the whole 70k. They were rusted a bit on the outside and the tips were either white or yellow. Never seen the tips of a plug yellow before? Anyway replaced them with Autolight Platinums. BTW don't pay $2.50 a peice at Advance for plugs, Walmart has them for $2.88 a two pack. I threw over $6 away getting them at Advance. At least I'll know next time. Funny as much as I hate Walmart I might have to start going there before I go to the auto parts store.