[x300] Throttle body cleaning

How often do these things need a swabbing? I had mine all nicely
tucked away by the dealer in late August, and the throttle is
sticking again just before idle (1500 rpm or so instead of 900 or
so). I’ve had trhe EGR recall thing done, and I assume the stiffer
spring was installed. It was fine for a while, and this past week
it’s sticking again. Is there something I’m missing, is there a
greater problem with oil or whatnot gumming up the works, or is it
time for a new throttle body? Thanks.

Greg
95XJ6–
Otto99
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

I’ve had mine apart for cleaning a couple of times, and give it a good
squirt with carb cleaner at regular services to keep it clean and keep the
idle smooth. Different cars seem to gum up at different speeds, and it may
be affected by the oil you use as well - in particular, I think the lighter
oils (0/30 etc) are more likely to cause the trouble.

Cheers - Jez> How often do these things need a swabbing? I had mine all nicely

tucked away by the dealer in late August, and the throttle is
sticking again just before idle (1500 rpm or so instead of 900 or
so). I’ve had trhe EGR recall thing done, and I assume the stiffer
spring was installed. It was fine for a while, and this past week
it’s sticking again. Is there something I’m missing, is there a
greater problem with oil or whatnot gumming up the works, or is it
time for a new throttle body? Thanks.

In reply to a message from Otto99 sent Thu 11 Dec 2003:

Mine is doing the same thing. I’m going to clean it again this
weekend. When I have it apart, I’m going to pull the crankcase vent
hose form the valvecover and flush it as well, this may reduce some
crud. I will also apply some PTFE (teflon)lubricant on the area
with a rag to see if a little slick will let the crud by (use a rag
to keep any liquid from running down the throttle shaft and getting
into the TPS). I will say here that I cannot see how the throttle
body would ever need replacement to fix the sticking problem. The
only part of the throttle body that can wear out is the throttle
shaft bore. Everything else on it is inert (there is a water jacket
that can crud up, but it can be flushed). I imagine the dealers
like to replace them to get the money and avoid the trouble of
cleaning, but it is not necessary if you have a little time to mess
with it. The throttle body service is one place where the shade
tree guy can save some significant money over the years. I imagine
that a throttle body that cruds up faster and faster is on the
receiving end of increasing blowby through the crankcase vent hose
which is purely a function of the engine getting older and rings
and valve bores and seals slowly wearing out. This is a slow
process and nothing to get overly concerned about.–
The original message included these comments:

How often do these things need a swabbing? I had mine all nicely
tucked away by the dealer in late August, and the throttle is
sticking again just before idle (1500 rpm or so instead of 900 or


Brian Caro
Newport News, VA, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

In reply to a message from Otto99 sent Thu 11 Dec 2003:

I thnk that if you operate at lower temperatures, due to a bad
thermostad as well as climate, it contributes to this. If your
temp guage is below the mid bar, change it. As Brian said, coolant
circulates thru the TB, so there must be a reason. Also, the
crankcase vent hose will crud up even on an engine that is in good
shape. Also, the external cleaning is a good routine thing to do,
but there is nothing like having it off every 50K miles or so.–
uncle
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–