I just had my electrnic control module replaced and found that my vacuum hose wasnt hooked up to the ecu when I hooked up the vacuum my car ran so much better but here recently it has started idling from 10thousand most of the time and sometimes 7 thousand pulses betweeen the two makes it kinda hard to turn idle down as it will die when it does this any ideas please help

 

The "could be" list is a bit long.

You "probably" have a vacuum leak ...which takes lots of patience to check for because of so many possible sources.

However, I'd begin by cleaning the throttle bodies and making sure the throttle blade gap is at the correct .002" clearance...followed by synchronizing the linkages. If the throttle bodies are not in synch you'll get a rolling idle.

Cheers
DD

 

To trace a vac leak spray locally one area at a time with start gas. If you hit the spot revs should rise and then sink when you stop squirting. Best chance of finding if you can squirt when idle is above normal but not really high.