Okay ive been having power issues and also idle issues. When i stop at a light the idle goes to normal but the longer i sit there the idle slowly bleeds off to where the idle screw controls it. Almost like thr iacv isny working but i jusy replaced it cause this problem. Could it be a vaccume leak? If so would this be causeing some power loss and also where and how should i check for the leak?

 

A vacuum leak would cause idle to increase, not decrease. Basically, low idle means engine is starved for air.


Suggest cleaning the throttle plate (both sides) w/ throttle body cleaner and bore around throttle plate.

Remove IACV from throttle body (leave coolant hoses attached) and clean inlet/outlet passages of IACV in throttle body to make sure they are not blocked.

If you pull the PCV connection to throttle body w/ engine running the idle should increase.

good luck

 

I cleaned the fitv and iacv. it idles good for about 5 minutes then it slowly starts to decrease to where the idle screw controls it. To about 400rpm if i unplug the iacv it doesnt change the idle. I just replaced the iacv thou. If i stop at a light it idles good but the longer i sit there it slowly decreases. Like the iacv is bleeding off and stops working.

 

Do you have Check Engine Light on? If yes, then get code/s and post them.

I would suggest branching 12v directly to the IACV and confirm that solenoid is opening w/ power and closing when power is removed. It could be a defective motor that is binding.

good luck

 

My car is cel free. And this is the second IACV i tried. Im gonna test the plug tomorrow with a volt meter. But something is causing it to leak off or slowly stop working at times. Ive been trying everything to fix this for a while. You can watch the rpm guage goes from 800 slowly down to 400 when i stop for a while. Its affecting the performace of the motor too. Something is causing the IACV to malfunction i think

 

Have you ever adjusted base idle? Disconnect IACV and adjust air bypass screw (TDC of throttle body entrance) to get 550 +/- 50 rpm's. Then reconnect IACV, reset ECU by pulling 7.5A BackUp fuse in underhood fuse box.

good luck

 

Yeah i did that the screw wont adjust it past 500 thou. Then i reset it and it works for alittle it idles at like 750 for about 10 minutes then it slowly drops back to 500 so i tried it again and when i disconnected the iacv again when it dropped to 500 the idleing dont change until i disconnect it and plug it back in. It stops working for some reason then it starts working again. Both iacv i tried do the same thing

 

The passages into/out of the IACV may be blocked. An electrical fault in IACV should set a code.

Try resetting the ECU to see if that helps. I am now purchasing my 2nd 94 EX ECU because of board faults. If you confirm that iacv is not being driven, then ECU fault is likely. You could rig a small light bulb across the IACV wires and tape to windshield. You should see the light winking on/off fairly rapidly. If not, an ECU fault is likely.

good luck

 

I got a whole new throttle body with all the valves on it i was gonna put on buy its alittle different. The top hose on the back of the throttle body has a plug on it where mine has a hose that runs to a black box and a silinoid thing near the front passenger head light so i disconnected my hose and put the plug in it and it seems to run alot better. What is that black box and why did that plug fix my power issue /idle issue cause i just disconnected the hose and used the plug off my other throttle body. Its weird. Any ideas?

 

The black box has EGR vacuum switching solenoid valve, and perhaps other components. I didn't find a good description in shop manual.

Not sure how plugging the hose fixed your problem.

good luck