My 98windstar 3.0li is losing power as i depress the throttle?

Question

the fuel filter is good, spark plugs are in good condition too.

Answer 1

There are many possible causes.  Is the Check Engine light on?  If so, get it scanned and have a competent mechanic use the code to diagnose the cause.  Possible causes include:

1.  Vacuum leaks

2.  EGR valve stuck.

3.  Oxygen sensor failure.

4.  Wiring issues.

5.  Plugged catalytic converter.

6.  Badly clogged air filter.

7.  Computer problems.

8.  Bad quality fuel.

9.  Sensor issues.

Most of these will fire a failure code and turn on the Check Engine light.  This will tell a competent mechanic where to start looking.  Don't start changing parts based upon the code since there are may possible reasons for any given code.

Answer 2

check your throttle body. it could be shutting completely when you lay off the gas when it should only shut partially