1999 Chrysler Town & Country (T&C) LXI 3.8 Spark Plug remove andreplace job

My van has 95k miles, I bought it used and did not know when/if the
plugs had been replaced, the plug wires were the Mopar original so
they and the serpentine belt were on the list for replacement.

I read newsgroups and AllTech for the how-tos and it came to a jump
ball on do the back plugs from the bottom or the top. I put the van up
on the ramps and looked at the situation from the bottom. With 95k
miles, I did not like the prospects when the instructions started with
"remove the resonator". This van has rear air and even with the
resonator (and the exhaust pipe) out of the way, access to the plugs
was ugly, especially when lying on my back. Even with a pillow of some
sort to hold up my head, the prospect was bleak. I saw the high
potential for the rusted bolts on the resonator shearing off and that
moved me to look at the top approach.

The top instructions started with removing the windshield wiper "box"
and some said you could then reach the back plugs. I found this not to
be true with my arms and the rear air tubing at the rear of the
plenum, so I ended up with a more extended process, but one that was
quite satisfying since I could attend to many details correctly. So
here is the "refined" process as I look back on it, eliminating the
several miss-steps as I worked through the maze of alternatives.

Pictures are available on the project gallery.

1) Remove the battery negative terminal.
2) Remove the 2 bolts that hold the hood latch and set the latch off
to the battery area. I learned this was a good thing to do after
leaning over this latch poking me in the belly for a long time. The
latch has positioning tabs, so there is no adjustment to mess up, just
2 bolts to get it out of the way.
3) Remove the windshield wipers. Loosen the nuts to be flush with the
end of the shaft and while pulling up on the wiper arm, give the nut a
shot with a hammer to release the arm from the tapered shaft.
4) Remove the cowl cover. It has 6 star head screws. You can buy a set
of tips that go into replaceable tip screwdrivers for cheap and do it
the easy way. There is a hose connection for the washer nozzles, pull
it off.
5) Remove the rubber seal that runs the length of the wiper box.
6) Remove the connector for the windshield wiper box, it is above the
battery. The connector has one of the red sliding locks and a push
latch to get it apart.
7) Disconnect the washer hose leading to the wiper box.
8) Remove bolts and nuts holding the wiper box and lift the box up and
off.
9) Remove the serpentine belt. I used a 15mm box end wrench with a 2'
piece of 1.5" PVC pipe on the tensioner roller and slid the belt off
the alternator pulley. I was replacing the belt so this step was
necessary. The alternator brace needs to be removed (even if you are
not replacing the belt) so I think the belt needs to come off under
all circumstances.
10) Remove the bolts on the alternator brace and remove the brace.
11) Remove the nut holding the ground strap from the plenum to the
firewall near the alternator.
12) Take a picture of the hose and electrical connections on the
throttle body so you can get this area back together later, then take
off all the hoses, connectors, and throttle linkage. The plenum and
throttle body are coming off and the wiring harness is staying, so
keep that in mind.
13) Remove the 2 bolts that hold a metal tube coming from the exhaust
system to the bottom of the throttle body area.
14) Remove the bolt for the plenum support brace that goes into the
cylinder head.
15) Remove the 4 bolts that hold the coil assembly to the plenum. Let
the coil rest next to the plenum, it will stay there when the plenum
comes off. Don't take off the wires at this time.
16) Remove a hose connection from the alternator side of the rear
valve cover. This hose runs under the plenum and connects to the PCV
valve near the throttle body. The hose will stay with the plenum, so
don't remove the PVC valve end of the hose.
17) Remove the bolts and nuts that hold the plenum to the intake
manifold and lift the plenum up enough to clear the studs and move it
towards the front of the vehicle about 2". Don't pull too hard since
the oxygen sensor is still connected to the plenum.
18) Put tape over the intake manifold openings. I used duct tape (what
else?) to avoid anything dropping in and wasting lots of time.
19) Reach behind the plenum and remove 2 13mm bolts holding the wiring
harness to the back of the plenum. See picture 002_6795 in the image
gallery. It shows the clips around the harness.
20) Use a mirror so you can see the oxygen sensor connector and get it
off the tab on the plenum. It is not necessary to disconnect the
connector.
21) The plug wires are held by a "C" shaped retainer on the alternator
side at the back plenum. Pull the wires out of the retainer. See
picture 002_6796.jpg lower left end of bracket on back of plenum for
what the "C" clip looks like.
22) The plenum will now lift off and clear the vehicle.
23) If you are replacing wires at the same time as the plugs, you can
pull all the boots off the plugs and take the coil assembly and wires
to a work area to swap the old wires with the new ones (one at a
time).
24) The rear wires have split-loom tubing over the wires, make sure
you have the tubing in place on the replacements.
25) With the plenum off, access to the rear plugs is just as easy as
the front plugs.
26) Before removing the plugs, use an air blast then a Shop-Vac to get
all dirt from around the plug to assure nothing gets into the
cylinder.
27) Put each removed plug on your work area in a layout similar to the
motor so you can examine all plugs and make comparisons for plug
condition. If any plug shows a problem, you will know which cylinder
it is.
28) Going back together is a reverse of the trip.
29) Use anti-seize compound on the plug threads. This good stuff on
almost all bolts since it allows you to hand tighten everything,
minimizing using a ratchet or wrench to take up long threads in
confined areas. It is very important for plugs as without anti-seize
future removal will most likely tear up the threads in the head. The
compound also acts as a lube to assure accurate torque when tightening
the plugs to 20-23 ft lbs. Don't guess on this, have a torque wrench.
30) The new plug wire set I bought came with heat shields for the plug
boots. The shields are necessary so make sure you have them installed.
31) Clean the mating surfaces of the intake manifold and the plenum. I
used a putty knife to get the old gasket off and GOO GONE adhesive
remover to get the deposits off. The surfaces should look like new.
Buy a new gasket, it was less than $4 and trying to re-use the old
gasket could ruin a hard job.
32) Put the coil, wires and plugs back on the engine, click the boots
on the plugs, get the wires routed comfortably in the wire clips.
33) Put the plenum back on the engine about 2" toward the front of the
vehicle of its normal position so you have room to put the 2 bolts
back into the wiring harness retaining clips and get the oxygen censor
back on the stud and get the plug wires back in the "C" clip.
34) That's it. I think barring any miss-steps it is about a 3-4 hour
job.

Corrections or additions appreciated. Good luck.

 

The image gallery is http://www.pbase.com/throck/van_plug_project -
the link didn't work.

 

What idiot designs such thing? Those stupid engineers were required to work
in a garage for a few years, before they imagine only one bold on a car.
(Jenne, Holland. 3.3 SE Voyager)

 

There was a time not too many years ago, where you *could* meet all
expectations for a vehicle with minimum and reasonable compromises. I
(who am an engineer) get as frustrated as the next guy when working on
my own cars - even to the point of cussing "the idiots who designed
this". But today, there are so many conflicting requirements
(lightweight, passenger safety, ease of repair, low maintenance, low
emissions, handles well, low cost, every convenience known to man,
including full scale workstation computers, etc., etc., etc., etc.,
etc., etc., etc.) that at least one would-be requirement - usually more
than one - has to be sacrificed. There used to be a saying in business:
"You can have it fast, you can have it good, you can have it low cost -
pick any two of the three, but you can't have all three." With today's
car, it's more like "There are 29 possible favorable attributes you can
have in this vehicle - pick 22 or 23, but you can't have all 29." At
best, you can have 28, but then you don't get low cost (number 29).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

I have the exact same 1999 T&C and have replaced the plugs myself 2x already
and the wires once. The front three plugs are a no-brainer. The driver
side rear is almost as easy from underneath. The passenger side rear can be
gotten from the top with appropriate swivels and socket extensions by simply
removing the alternator bracket (no need to even loosen the alternator).
The center rear is a royal PITA and takes more time than all the others
combined. I get to it from underneath the vehicle by reaching in pretty
much blind and getting my socket with extensions. Last time I got them all
in about 90 minutes and had the scraped up hands and arms to prove it
afterward.

Good thing these platinum plugs seem to last ~4 years.

Good luck.

Bob

 

lets get real
your are told to build as cheap as possible and to get it down the line as
fast as possible and then everything else falls were uit may

 

Sort of. I'm talking about on the design end (which of course, when
done properly, does also take into consideration the costs of
manufacturing). When it costs no more to design it right *WITHOUT*
incurring additional non-recoverable costs for the manufacturer (and
hopefully the consumer, although costs to the manufacturer generally
trump consumer hidden costs - such as to use a timing belt vs. a timing
chain), then generally speaking, the better design will be used
considering all "29" ( a hypothetical number I made up for discussion)
"niceties/desirements".

Certainly some stupid things have been done by the manufacturers that
could have cost zero, or even created savings, had good engineering and
economic judgement been allowed to prevail (example: 2nd gen LH cars
using non-standard straight-base headlight bulbs instead of the standard
angle-base bulbs when there was absolutely zero reason to come up with a
non-standard bastard part used nowhere else in the industry that is
otherwise the same bulb - i.e., there is not a space problem and the
details of the headlight assy. to accommodate either type bulb are
arbitrary with zero recurring cost impact to produce the headlight assy.
- and non-standard anything (bulbs in this case) always cost more).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

I agree about the compromises and understand that the engine,
transaxle, drive shafts, struts, brakes, etc. (the whole drive train)
are all put together as a sub-assembly and then married to the body.
So since the engine was not assembled in the body, maintenance in the
body for some things is potentially impossible without significant
disassembly.
I put the original message on the newsgroup for those that need a
longer but less physically demanding and damaging approach to the
problem. From what I have read, the next generation vans have
corrected the serviceability problem.

 

Nothing will ever be as bad as the #3 plug on the old VW Beetles. There were
more than a few I worked on that had the #3 plug much older & a different
make than the other three -- obviously many gave up trying to replace it...
(Some folks dropped the engines to do tune-ups, that being easier than
trying to reach that one plug in situ.)