This vehicle belongs to a friend of mine. IT's a 1998 E250 Ford van with 5.4L automatic. It's an old Hyster service van, he bought 5 or 6 of them various years. He brought the van over with a bad miss. Check engine light was on so I pulled codes. It was a missfire cylinder 1. So we decided to put plugs and boots on it. The plugs had never been changed the van has 220000 miles on it. I changed the plugs and boots and it doesn't run any better, the light is still on.

Here's where I need help, it now has a code P0354 Ignition Coil D Primary / Secondary Circuit Malfunction.
Can someone give me some info on what I need to do?

Thanks,
Delos

 

that would be a bad coil on cyl 4.when you chang a plug for a miss the coil should be changed not just the boot.

 

However his original problem was with cylinder #1. Since you had all the COPS, boots, and plugs out, this code is likely that you didn't get the COP electrical plug on good, on the #4 cylinder. A COP failure would "usually" give you a P0304.

Check the electrical plug. If OK, swap the COP with one from another one you can get to easy, and make sure that the code shows it moved with the COP. COPs are too expensive to take a chance, IMHO. But I'd give it about a 99% chance its the plug. Don't just push it in either. Look in the plug and the COP to make sure you didn't break off or bend something on reinstall.

 

Thanks!

I check out the plug connectors tonight. Yes the original misfire was on #1, however when I reinstalled the COP's I put the one from #1 over on #5 just in case it was possibly a bad COP.

I bet you are right, I didn't get it plugged in good or possibly bent the connectors.

Thanks again,
Delos

 

That's what it was, not making good connection. Looks like I didn't get the plug pushed all the way on.

Now if I can just get the A/C figured out on this thing, I can get it out of my driveway.

Thanks,
Delos

 

Thanks for letting us know it worked. It's always nice to know if I was guessing right.