Question about throttle body cleaning on 97 Cherokee

It seems like every time I take my 1997 Jeep Cherokee Laredo (now has 36,000
miles) to the dealer, they tell me my throttle body has sludge and needs
cleaning. The last time they told me that was not too long after they
previously did it.

Is this an easy way for them to get more money? Should I be worried about
this? Is it something I (i.e., really easy) can do?

Thanks!

 

I don't know, but my 1995 YJ with sixty thousand miles hasn't needed
throttle body cleaning yet. I did it once, but I don't really think it
needed it...

Earle

 

Ted,

If you do in fact need the throttle body cleaned, www.allpar.com has a
procedure posted for doing just that. You have to spend a couple of bucks
on some throttle body cleaner and takes a little bit of your time. There
was a noticable difference when I performed this on my 2000 TJ, it was like
night and day.

Below is the porocedure.

Hope this helps,

Greg

Greg Smith posted this at Neons.org. It was not written by John Mastriano!

Mopar Combustion Chamber Cleaner/Conditioner is really good for removing
carbon deposits...The following directions outline the way that professional
mechanics have been using the cleaner for years -- they were finally
published in TSB 18-31-97 for 1996-98 Jeep 4.0 Liter misfire conditions:

1.. Operate the vehicle until the vehicle reaches operating temperature.
2.. Remove the air tube from the throttle body.
3.. With the engine at an idle, spray the entire contents of Mopar
Combustion Cleaner, p/n 04318001, directly into the throttle body. Allow the
vehicle to load up with the cleaner to the point of almost stalling out.
4.. Shut the engine OFF after the entire can is ingested.
5.. With the hood closed and the vehicle parked inside the garage, allow
the vehicle to soak for two to three hours. This will ensure that the engine
will maintain its temperature and will allow proper solvent penetration.
6.. Drive the vehicle on a highway/freeway that will allow the vehicle to
be driven safely at the posted speed limit. Upon entering the
highway/freeway, accelerate hard to the posted speed limit and maintain
speed. Slow down and then perform 5 to 10 Wide Open Throttle (WOT) upshifts.
Continue driving at the maximum speed limit for 1-2 miles (if conditions
allow).

 

Check the air filter for oil. If the CCV system is plugging up, the
blow-by is vented to the air filter box then swallowed thru the
throttle body. The more crankcase fumes it swallows, the faster it
gets dirty. I treat the throttle body cleaning as an annual
maintainance item - if you catch it before it starts to plug solid,
then all it takes is pulling the intake hose and a few minutes with a
can of spray cleaner. If the blow-by is getting pretty bad or you
ignore the cleaning it will plug solid enough to need a full soak
(with a few dril bits) to clean the throttle body.

 

The air tube is the flexible hose about 3 inches in diameter that runs
from the air cleaner box to the top of the throttle body, which sets
on top of the inrake manifold. It's held onto the air cleaner box
with a clamp and onto the top of the throttle body by 3 small screws.
For cleaning, take it off and get it out of the way.

You want to spray 2 basic places: into the main bore, where the
butterfly valve that attached to the accelerator lives, and into the
idle air control valve openings. The throttle position sensor (and
the sensor for the auto xmission, if used) mount on the shaft that the
butterfly is mounted on, the IAC is the other gizmo that has wires
connected to it. The plunger on the IAC will gum up as well as the
port it fits into, so you sometimes have to pull the IAC off and clean
it specially, especially on some of the older ones. Open the
butterfly and look for a ridge on the wall of the bore where the
butterfly plate closes - mine had a build up of a good 1/8 inch when I
first got it that took scrubbing with cleaner and a tooth brush to
remove (I was surprised it even ran it was so gummed up!).

I do mine about once a year, but I've got a fair amount of blowby with
155,000 miles on the clock. If it's really dirty, check more often
and just clean as needed. The need will be fairly obvious.

If it looks pretty dirty, also check any other passages you see -
especially the one where the MAP sensor hose connects.

 

I also recently had the dealer recommend the throttle body cleaning, for
around $180 (this was at 30k maintenance).

What is a reasonable price for this work if one were to pay 1) any
mechanic or 2) a dealer's service shop?

 

Is this the one where you spray the stuff in until the engine
darn near chokes, then shut the engine off and plug any intake
hole you can reach for a coupla beers ^H^H^H^H^H hours and let
it soak the gunk off? Have a smog inspection on a 4.0 ZJ
coming up soon and California has a new procedure that I
strongly suspect is intended more to fill the wallets of
the state and the repair shops than it is to reduce smog.

 

P.S. The 3M directions don't say to let it sit for that long, seems like
it's no more than a few minutes, maybe ten at the most.

Jerry

 

Since all it takes is a spray-can of Berryman's B-12, some paper towels,
and 10 minutes, I can't see paying one nickel for it.

 

the can of cleaner cost under 10 dollars and takes 3 hrs if following the
directions because once the contents of the can is empty the car has to sit
for 3 hrs. but most techs don't do this and charge a hours labor
it's a rip off if you don't have any idle issues