Help

[1sikgs]

hi all,

i need a great deal of help. recently i have been having a problem when i turn the car off. the motore kind of shakes and sputters a little before shutting off. it doesn't do it at any other time. what could the problem be. it's a 2000 GS300 and i just hit 60,000 miles a couple of weeks ago.

[GuyTelefunken]

There is a condition called dieseling which used to be very common years ago. This condition manifests itself by the engine continuing to run or somewhat run after the key is turned to the off position. It can be caused by carbon or other deposits found in the throttle body or inside the actual cylinders.

If there are deposits in the throttle body, they can cause the the throttle plate to not fully close when the engine is turned off. Air leaks by the plate for a moment after turning off the key and the engines continues to try to run on the gases still trapped in the cylinders. Deposits in the cylinders can remain hot after the key is turned off and cause the same condition.

If you dissemble the throttle body and find a fair amount of contaminants, I would suggest cleaning it with carburetor cleaner. There is also a product called gum-out which is for this purpose. If upon reassembly your problem is gone, you're done. If you continue to have difficulties, I would suggest a trip to a qualified dealer to diagnose possible other causes.

On your engine you must first remove the plastic cover and then the intake hose on the passenger's side. The throttle plate or butterfly as it is sometimes called is located fairly deep in the throttle body. More dissassembly may be necessary to clean it.

It isn't extremely likely that this is the cause of your problem but it is possible.