Could it be the O2 Sensor?

[Todd Young]

Use an analog volt meter (type with the needle), and set the voltage to 
be able to read low voltage, the O2 sensor puts out between 0.5 and 1 
volt. Hook the positive lead to the signal wire (black in think on a 
three wire, two whites are for the heater coil), and the negative lead 
to ground.

Fire up the engine, once warm, the needle should continuously bounce 
between 0.5 and 1 volt. It's too rapid of a change to be accurately 
reflected with a digital voltmeter.

Another test is to find a nice flat stretch of road and set the cruise 
control. You should feel a nice steady ride. If you feel "surging" then 
the O2 sensor is shot. Surging is where you feel the engine accelerate, 
then let off, over and over. On a flat stretch, the cruise should be 
able to hold the engine pretty steady, with no surging.

Zsolt wrote:
> speaking of which...is there a way to test the O2 sensor itself?
> TIA, Zsolt
> 
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-- 
Todd Young
7079 Dawn Ave. E.
Inver Grove Heights, MN 55076