Hello, I have a 1998 camry with the 5sfe 2.2 engine in it. The vehicle surges 80% of the time and the other 20% it is perfect! Sometimes when I surges it runs rough while at speed also. There is 280000 klm on the clock. I have tested and cleaned the idle speed control valve and tested ok. Spark plugs are new. Air cleaner is ok. Cannot find any vacume leaks. Engine light is not coming on. Any help would be much appreciated.

 

I forgot to say that it surges at idle, also sometimes it idles between 900 and 1000 rpm, when it idles high it stops surging and idiling rough though

 

Might check the fuel pressure regulator. Could be too high or low pressure (or both), the regulator not doing its job.

Sometimes a pickup coil for the ignition system can have problems.

When it surges (car stationary) try shifting to Neutral and determine what happens.