This sounds very similar to a problem that I am currently having with my XJ6. After stopping at a red light I pull out and about 3 to 5 seconds later RPM's die down to around 1000RPM and stay there for a few seconds and then it goes and all is well. It does the same thing when I am at a constant speed and accelerate quickly to pass for instance but when driving normally it does not seem to be an issue. I will be checking the fuel filter and O2 sensor tomorrow to see if this is the cause. Thanks for the good info. <openhaynesmanual>research</closehaynesmanual>.

 

As a side note this happens more often when the engine is warm or has been running (normal operating temperature) but does not seem to be an issue when it is cold or not up to operating temperature yet.

Any ideas or suggestions definitely welcomed...