So previously I mentioned I had a slight misfire on cylinder #6 (PO306) which occurs on cold starts & in really wet conditions. I cleared this & about 3 months later CEL came back, since I really dont want this worsening over winter, I decided to get the plugs out and take a look-see. Well, the plugs look pretty good but I noticed that on the Bosch platinums, the centre electrode is worn below the insulator & a slight layer of combustion deposit occurs on the tip of the center electrode, making the tip not visible with the naked eye. The job was going really well & the second bank of plugs (I did these first to gain some confidence) I had out & refitted in about 2- 2/12hrs which is about twice the speed It took first time I did this job. However upon inspection of the EGR tube which I removed to access the rear plug I noticed the lower compression joint (flare) of the EGR tube was missing & later found this under the van it had sheared off when I undid the retainer nut

Good job this is not an expensive part, although I have to wait a few days to get one since it's our thanksgiving holiday over here!
Ive fitted Motorcraft plugs which are about $5.36 each instead of the $4.50 for the Bosch units.

The 1st bank of plugs (#1-3) I accessed 2 of them through the wheel well . They were a bit of a breeze compared with the rear plug, which is a right royal nightmare! However with the doghouse off & laying on my back with right arm through the cover I can reach the boot & it popped off without too much problem. Then I had a bit of a puzzle to figure out the correct angle to get the socket & wrench on the plug. I found that a fairly short straight handled 3/8 drive got me into position with about 3 clicks to spare on the ratchet ! Got the plug out without incident,.... then comes the hardest part. To get that plug in you have to be somewhat of a contortionist! What I did was this, engaged the plug into the socket & with right hand & plug facing back towards my wrist, (plug & socket cupped in my palm) deft hand movement coupled with near cnc control.....managed to thread that sucker right into the plug hole first try!!!!

Rather pleased with my skill or luck as may be, the entire job taking about 4.5-5 hrs...... not braking any records but well worth the $500 shop price!

Happy re-plugging
ATB Aeroman.

P.S I also took some time to clean & inspect the wires & they look fine by eye, so I'm pretty confident that the plugs are the problem,,, time will tell.

 

good job, lots of fun
i like to do it in hot weather, can take lots of breaks under the shade tree laying down in the grass drinking a cold one
slows the knuckle bleeding down and relieves pain


Ford recommends using anti seize compound on the plug threads.

i use gobs of dielectric grease in the plug and coil pack boots, prevents heat welding to the plugs.

there is a plug wire resistance measurement test that measures the special center conductor resistance per manuf. specs; located in the old threads. doesn't tell a think about insulation breakdown though which is the major problem with Aero plug wires especially on the 4L used for heavy towing with lots of heat.

 

Yeah, I put dielectric grease in the plug boots. The anti-sieze wont hurt as long as you dont go overboard with it! Last time I kept the plug threads dry & they came out without any problems.
BTW the Bosch plugs went about 65,000 kms, lets see how the Ford ones last.

 

All I have to say is that BOSCH SPARK PLUGS ARE JUNK...!!!

 

I have found it is much easier to get the rear passenger plug out from underneath the van. Going through the doghouse is way to tight. I still remove the cover so that I can see. I can change all the spark plugs on my moms van in about 45 minutes, excluding cleanup time.

 

I guess I'm the only one who can remove the rear passenger from under the van by reaching around the passenger exhaust manifold?

The doghouse door is way too tight I think that I would need an extra 2 joints on the my wrist to work that miracle.

The worst one for me was the drivers rear compared to that the passenger was nothing.

Having to slip a socket over the hex on the spark plug socket due to clearance issues is the most annnoying thing.

 

I changed plugs in my '94 4.0 extended 2WD about six weeks ago. This is my fourth Aero. I took both front wheels off and the doghouse door. I took the doghouse off just to get more light in so I could see better. I don't know when the last time the plugs were changed because I purchased this van used.
A couple of days later I had to make a 2000 mile trip for a funeral and on the 400 mile stretch that I checked, I got 25.2 MPG. This, of course, was on a fairly level highway, but the van was carrying three adults and two kids, plus loaded to the gills with luggage.
Actually, with the right tools and a little patience, changing Aero plugs is not too hard.

 

I do it that way too. I can change all of my plugs in less than an hour. I wouldn't want to make a career of it though.

 

Me neither.

I can still remember the scrapes and cuts from doing it the first time.

But now I can get through it without leaving too much skin behind .

 

i only give at the Red Cross now

Harbor Freight Tools - Quality Tools at the Lowest Prices

 

My van was the first time i ever changed sparkplugs, and it took me about an hour and 15 minutes. I did all of them from the front except for the rear passenger side, which was easiest from underneath the car.

 

I still have a few scares from the first time I replaced the plugs on my 3.0. The right side rear was the hardest. Aeros are not that hard to work on 'just differant" .

 

I avoided scars by wearing gloves....for me the hardest part was actually getting the boots off of the plugs. dialectic grease should make my life easier next time

 

45 mins thats quick!!! 7/8 mins each you should work in the trade (you probably do that right?).
I think if I ever do them again I'll try the rear passenger plug from under the van, since it took about an hour messing around with the doghouse & replacement of it etc. The rear driver plug #6 was no problem at all once the EGR pipe is removed. I do tend to remove stuff for better access, though this time it cost me , since the EGR pipe was rusted & broke. No-one around here has the pipe so I'll probably have to fab up something to repair it, good job I'm machine shop handy
The only place so far I've found who has it is a sponsor of this site, (Y2K Ford parts) so I've ordered one just incase!
Aeroman.

 

Wow, I guess having long arms pays off on Aero's. I change my plugs from the front of the vehicle. I only remove the nut holding the oil filler tube brace and swing it to the side to get easy clearance for the passenger side plugs. The drivers side rear does take a little more time, but I just reach back there and git er done. If I remember, I put the socket on the plug then used a rachet with about a 4 inch handle (little short rachet). I did learn to wear long sleeves to avoid scratches from the throttle cable assembly. But, I changed all six in my 94 3.0 in about 30 minutes. I went thru the doghouse for the wires and cap, etc. I simply could not reach the drivers' rear plug thru the doghouse. (arms too long, I guess...lol)
I replaced my plugs, wires, cap, rotor, and Air Flow Meter last month, plus $300.00 for tires. Just turned 255,000 on the old girl. I really need to get my suspension up to par. Bushings all going bad. Need new shocks too.

Plus, last month a guy flew in off the street into the gas station, and hit my Right rear just above the bumper, left about a football sized dent. Then the next week, as my wife pulls out of her job, a motorcycle comes over the hill too fast, has to lay it down, and ends up with a football sized dent just above the drivers side rear bumper. So I have two dents almost identical on both sides now. Then, the next week, I backed into the mailman's truck (he snuck up behind me) and busted up my rear bumper skin IF that wasn't enough, I got a rock from a dump truck, so now I need a new windshield. Arrrgh!!!!

M