Rpm drops

[90Integrab18a1]

I have a 1990 Acura Integra GS with 189,000 miles on it. I've had the car for about 4 months and it's had a weird RPM drop when I touch the gas. I get it to about 2500 rpm and when I let off it drops to 1000 really quickly and then it dips to about 250 Rpm, almost like its about to shut off. But after that it idles fine and nothing else is wrong with the car.. Help!

 

[SbS91TeG]

You can try cleaning the iacv and I believe you leave it unplug and adjust the idle screw on throttle body then re connect engine should also be at operating temp before adjustments. Mine was doing that so that's what I did.

The map or tps could also be bad and may need to replaced. What's the vacation at idle? Tps can be back probed with t pin or safety pin center and top terminal volts should be little under a volt at idle under 5 volts at wot engine does not need to be running. Map sensor voltage depends on vac at idle and not sure of what it should be vacation should be 17-21 in hg you'll have to research what voltage should be back probe the back of map sensor connector like tps

 

[SbS91TeG]

You can try cleaning the iacv and I believe you leave it unplug and adjust the idle screw on throttle body then re connect engine should also be at operating temp before adjustments. Mine was doing that so that's what I did.

The map or tps could also be bad and may need to replaced. What's the engine vac at idle? Tps can be back probed with t pin or safety pin center and top terminal volts should be little under a volt at idle under 5 volts at wide open throttle, engine does not need to be running. Map sensor voltage depends on vac at idle and not sure of what it should be vac should be 17-21 in hg you'll have to research what voltage should be back probe the back of map sensor connector like tps