Replaced plugs...jerky

[rollinstone]

OK..replaced plugs...Autolite Double platinums. Gap: .054. The old plugs and wires were Motorcraft and had only about 45k on them.

Altho I replaced the wires when I put the Motorcraft plugs in, I did not do so with the Autolites thinking that...heck at 45k the old Motorcraft wires should be OK.

Now, when I'm driving up a hill at, say, 45-50 mph, the engine stutters/misses a few beats unless I disengage the overdrive, shifting me to a lower gear to get the speed up. Also noticed the engine bumps a little at idle.

I've checked, rechecked, and checked again to ensure that each wire is fully seated (the angles are kinda tight to get a good grip)...no help.

Thoughts?

 

[SoNic67]

On my 5.0L I am using Autolite XP104 with no issues.
The other option was APP104. If you look for the "Competitor Cross Reference" at Motorcraft you will see some differences.
Original ones on my Ex where Motorcraft AGSF-32F-M, listed only in the XP104 reference list.

Didn't replace the wires.

 

[rollinstone]

Yep...the Double plats are APP104s. They may be going back...I've had it! I'll put the old ones back on and see if I still get the low end jerkiness.

 

[noruckus]

any up date on this rollingstone, I'm having the same driving issues.

 

[xglyphicx]

I tried putting other plugs into mine.. went right back to motorcraft. My 97 HATES other plugs. In fact I put some bosch plugs in once and got a cyl missfire code on all 6 because of them. Dunno if this is much help.. but I won't put anything other than motorcraft in mine

 

[SoNic67]

Bosch plugs are running extra hot - their official "heat rating" is way higher than what's recommended on this engine.

 

[2k five-oh]

@Rollinstone--

Check that you are getting good spark from all of your wires...I had the same problem and I replaced my plugs thinking that would take care of it. It didn't. I talked to a Ford mechanic and he suggested I try replacing the coil packs, and that did the trick.

 

[rollinstone]

I WAS going to put the old Motorcrafts back on, but wifey tossed 'em out...serves me right for putting them in the garage trash bucket...WHERE SHE NEVER GOES!

Anyway...I went back under and pulled all the plugs and regapped them from a loose .054 to a very tight .054. I double checked all the connector caps. Noticed one of the caps had a tear in it, right about where you'd grab it with a puller tool. I couldn't tell if it went all the way thru, but I put a couple of wraps of electrical tape around it and reseated it firmly, as all the others.

Test drive seems to be OK now. The real test comes when going uphill with two kayaks on top with a load of paddling gear...

I'll get back with ya on that...