Wow, I like the 4.2 but never knew this. Duh. It does raise a lot of potential for a lot of odd questions though. lol

 

Remember, the 3.8/4.2 Ford v6 Essex is a knock off Buick 3.8. The Buick's had the first of the waste spark designs in their 3800 motor.

It would stand to reason, since it's a Buick design, with a Ford name, it should carry the same firing characteristics that the GM engine had.

 

The 4.6 in my F150 is the same thing. Lots of Fords (and GM's) were like this when they went distributorless.

Hell, even the last version of the pushrod 5.0 was a waste spark.

 

Right. This might be odd but?? This has me wondering if this may not be a random acceleration issue but a random relief from the loss of power and power is just returning to normal issue. Could this actually be a DPFE sensor fault showing up as a lean code?

I'm going to pull out the manuals and look at the valve overlap. The 4.2 has the funky, 2 piece intake with the plenum. I didn't understand why you asked about the Plenum White. I do now.

 

I'm thinking now, since he's changed the EGR valve, and it doesn't stall out now, changing these plugs to new should cure 90% of his hesitation. We can be sure when he pulls the other 4 out and posts them. Those are way beyond the 054 that the gap calls for. I'm crossing my fingers that this is his most prevalent problem at this time. As long as he has good compression, this most likely has to be the culprit.

 

I went out and checked the electrode OD on some of my old plugs and they average between .030 and .040 (different plugs). If that's what's being seen in these electrodes they are way over .054.

Nothing in the manuals about lift and duration.

 

Where are you located Maniak?

 

Sorry! I just got back home. In addition to dealing with my truck I'm also in the middle of getting settled in my new house and fixing up my old house to sell and today was the only day I could get back over there and finish up the last few things.

I just got caught up on what everyone has been saying. The plugs that are in it are definitely Motorcraft Platinum, but the writing is so faded I can't really pulled the model number off to look them up. I do have a gap set tool and I'll check them tomorrow since I'll be home all day and I should have plenty of time to pull the rest of the plugs and I'll upload the pictures. Based on how the first two looked, I was thinking I should go ahead and get new plugs and one of the wires when I looked into the plug I could see a bit of corrosion deep in the plug wire so I'll probably go ahead and get new wires while I'm at it.

https://shop.advanceautoparts.com/p/...034%7CL3*16071

Those were the plugs I was going to pick up, it says the standard gap is .54. I know I've read a lot about people having trouble with anything but Motorcraft plugs so I figured that's what I'll go with.

As far as codes go, since I bought the truck it never threw a CEL until recently. It would stumble and hesitate and stall, no codes. The only one I ever pulled was the P0113 for the IAT Sensor which hasn't come back since I replaced the sensor. It wasn't until I replaced the DPFE that I got my first P0174 for Lean Bank 2 and I got it again after replacing the EGR valve.

I'm located in Hubert, NC.

I've run countless tests with my Autel Maxicom and can't get anything to show up. I even checked the live data after driving it awhile and kept it idling while looking at it. PCM didn't register any misfires on any cylinders but I did see a total tally misfire rate of 5% which was odd considering every cylinder was 0% misfire rate.

I'll let you guys know what I come up with tomorrow with more pictures!

 

Go with Double Platinum for better life. Platinum only has the center electrode as platinum, whereas the Double Platinum gives you the center and side electrode..... which is why I think you have that abnormal wear with it being waste spark.

 

Alright folks.

#1 .45 gap
#2 .51
#3 .51
#4 .47
#5 .42
#6 .45

I replaced them all, set the new plugs to manufacturer specified .54 and put in fresh plug wires. I'll do a test drive later when my wife gets home.

here's plug 1

plug 2

plug 3

plug 4

plug 5

and plug 6


The numbers are matched with their cylinders. They're all really rough, some more than others. We'll see what happens during the test drive! (Also, in relation to the first two pics I posted the other day. The top pic was 4 and the bottom pic was 5)

Oh and, don't get freaked out by my middle finger nail, it's not abnormally long or anything. Part of my finger got cut off when I was a child many eons ago so it just grows funky lol