Chrysler Repair: Throttle Body Cleaning, air intake hose, magnum engine

Question
Roland,  My question is about the throttle body on the 318 engine. It happens to be a 97 Dodge, but since that's a Chrysler product I hope you are familiar.  Here's the problem.  My 318 magnum engine in my 97 Dodge van occasionally gets a problem where it doesn't want to idle. Cold or hot doesn't matter. When I take it in to Dodge for this problem the fix always seems to be, "we cleaned the throttle body".  What I want to know is what is involved in cleaning the throttle body, as I'm in a small town a long way from the nearest Dodge dealer. If it's fairly simple to do I'd try cleaning it before taking it for service. Also, is there any way to test the idle speed motor without a lot of equipment?

Thanks for your expertise.  Denis

Answer
Hi Denis,
I don't have any info on the modern V-8, just an '83 shop manual which does have an early FI set up. Thottle body cleaning can be fairly easy if you can remove the air intake hose that feed the throttle body. Then with a spray solven you can spray fluid in the thoat of the thottle and clean the barrels and the the back sides of the the throttle butterfly valves and also the air by-pass side passage that is supplying air controlled by the idle speed motor. The idle speed motors consist of two coils, so all you can do is verify continuity between the ends of the coils at the disconnect plug for the motor. So you should find four pins on the plug and they should have very low resistance between two pairs, and infinite resistance when you try to mix the pairs that you test. The other side of the disconnect goes to the computer, so about all you can do is look at the wires to make sure the insulation isn't melted in that area that you can trace which would  cause a defective motor control. Also if there is something wrong with the idle motor a code will be set in the engine cotroller memory for that fault. I believe that '97 was the last year where you could readout the fault codes with an ignition key (on-off-on-off-on and leave on, doing this in 5 seconds or less elapsed time) then watch check engine light to begin flashing, pause, etc. Count the number of flashes between pauses. Group the numbers in pairs to form two digit numbers which are the fault codes. If this doesn't work then you have to get a readout with an OBD-II reader.
But if you can get to the opening of the throttle body you can try to clean it yourself with removing it, using spray carburetor cleaner from a pressure can, rags, q-tips, to clean away any crud that is prveneting the butterfly valves from closing all the way, or crud in the by-pass passage entry hole where the idle speed motor controls the amount of air that enters the manifold when the butterfly valves are closed all the way.
Roland