Having problems after starting,, reg idle then high , then low then high.
I changed motors, 1.5l 91 CRX. anh help??
Rich

 

Be more specific. Does the idle fluctuate more when the engine is cold (i.e. goes above spec and then surges)? Or is the idle more erratic when the car is warmed up? Is it simply on startup? Elaborate and you may get answers....

 

vac leak
air in ur coolant system
bad IACV

got any CEL's?

 

Check your IACV isnt clogged. Mine did this too but it was a vacuum leak near the throttle body from the MAF

 

IACV could be the issue if its filter screens are contaminated with soot, thus causing poor air flow (dirty or cheap air filter would be the source of this). A FITV (fast idle thermal valve) can cause an incredibly high [or low for that matter] idle during cold startup which may cause erratic idle surges as the PCM tries to compensate for this misadjustment [which is actually a massive, internal vacuum leak]. Vacuum leaks are another main source to look at (failed gaskets/hoses).

 

thank you All, I started the car,, ran fine for a few min, then it just started reg idle to high idle (from 650-700 rpm to 1350-1500rpm) and it has not stopped,,,, Do the make a rebuild kit for the IVAC? and I am getting fault codes 10 and 14,,, still getting use to the Honda not used to cars with computers,,

 

checked for Vacuum leaks,, none that I can see,,, would a rebuild kit for the throttle body
help??

 

Guys,, thankx for the help,, my CRX is running fine. Again thank you
Rich