I have a 98 Windstar 3.8. For the past six months my engine light has been on and off. The Ford dealership has replaced my camshaft synchro and my electronic control module. These are the codes that came up when they hooked it up to their machines. The van also hesitates when I accelerate. My light is back on and the hesitation is worse. I took it to an independent mechanic, and their machine came up with two codes - a #3 misfire, and code 1538, IMRC stuck open. The mechanic checked everything he could without pulling everything apart, but he found nothing wrong (with the misfire). I put new spark plugs in when this problem started, and it cured it for about a month. Now the hesitation (misfire) is back. I think the misfire is worse when it's damp outside.

Also, I've got a popping sound from the front end. In the past it only happened when accelerating, now it's constant, even while I'm driving. A while a ago a Ford guy told me that a weld pops loose in the front end of these things. He thought that was the cause of it. Like I said, now it's constant, and I'm worried about driving it on the interstate.

Any suggestions?

 

If it's worse when it's damp outside, I would try a new set of plug wires. No idea on the popping sound.

393c Stroker

 

I would guess that something more is wrong if it is going through plugs that quickly. Have you checked compression? This would atleast narrow it down to eliminate valves or cylinder rings as either of these could cause plugs to go bad quickly along with activating your check engine light at times.