Eddie 70

I am trying to figure out if my IACV is even working or not. I have the issue where the car will surge around 1500 RPMS and I am trying to correct it. I measured the voltage at the connection to the connector and it is about 5VDC. I measure the resistance of the IACV coil and it is around 11 ohms. While I had it out, I connected some jumpers to the IACV and touched it with a 9V battery to see if it would move. I can see the plunger move but it is only moving about 1/8" or so if that much.

Has anyone checked one of these things that is working and can you tell how far the plunger is moving? Mine seems to be working like this.

This is on a 93 Del Sol SI, D16Z6.

grumblemarc

iTrader: (4)

Did you clean it? You didn't say. You only say you took it off.

Eddie 70

I cleaned it a couple of weeks ago with some Simple Green soaking. Did that for a couple of times. Each time was about an hours worth of soak time. Several rinses in between each soak period.

Do you think it could be still frozen in place and need more soaking? I have no idea how far the valve itself is supposed to move. I don't guess it would hurt to let it soak more and then hit it with the 9V battery while it has the Simple green in it. Could help to break it up some.

Eddie 70

Been soaking it for a couple of hours now in Simple Green. Also I have been hitting it with the 9V battery and cycling it about 10-15 times in each direction. Will see if it makes a difference tomorrow.

Former User

Do you have an IACV CEL code?

MonkeyMagic

i'm leaning towards fitv...

cause it's definitely leaking air into the manifold somewhere

Eddie 70

Right now there is no CEL. I assume that means there are no codes stored.

Eddie 70

Is there a way to check the FITV to ensure it is doing what it is supposed to do? Similar to what I am doing for the IACV. I have cleaned the FITV and screwed it all the way back down in towards it seat.

Former User

When there is a surging idle problem, remove the intake and then use your finger to cover the port in the throttle body leading to the FITV. Does this eliminate the surging?

Eddie 70

The surge is not during the idle. It is when you press down on the gas pedal and try to run the engine speed slowly above 1500 RPM. Easing down on the gas pedal makes the motor start to surge around 1500 RPM. The surge will go away and the speed will jump up to around 3000-3500.

Eddie 70

I let the IACV soak over night in Simple Green. Rinsed it out very good. Tested it several times with the 9V cell. It still works like it did yesterday so I am going to assume that is the only amount of movement out of the IACV and it is good.

itsmejto

A 9v battery cannot supply the current needed to test it.

Eddie 70

Just made a discovery. It looks like someone has painted over the CEL. So I pulled the cluster and sure enough it is covered by probably sharpie ink. I clean that off and shine a light through the back of the cluster, still no CEL glow. So I dig further and find a small piece of black tape over the CEL. Pull the tape and shine the light through and now I can see the CEL glow. Now that I have it all cleaned up and back in the car, the CEL comes on and stays on with the car running. Next up for the check is to pull the codes and see exactly what is there.

Stay tuned. I just thought this was a non-molested car.

Eddie 70

Looks like it is showing codes 1 and 14. Would it make a difference if the car were cold vs. warmed up?

Eddie 70

To correct this should I get another O2 sensor or drive it first and see if the code goes away. The car is currently getting around 35MPG.

foo fighters

you should clear you codes to see if you fixed that code 14 (IACV).

Former User

As mentioned, reset the ECU and then drive the car to see whether none, one, or both codes return. You only want to troubleshoot codes that repeat. Post any codes that repeat.

Eddie 70

I finally got some time to work on the car again today. I have cleaned and cleaned the IACV several times. Got to checking voltages to make sure I had no problems and found at some point down the line someone had plugged the TA plug into the IACV and the IACV plug to the TA. Now the car drives like it is supposed to and no more 14 code. The IACV appears to be working correctly. Woo Hoo.

Now I still am showing a Code 1. Which is an O2 sensor problem. I do have .4 volts at the connector when I turn the key on. I have tried the reset procedure on the O2 sensor mentioned in the manual and no luck yet. Any more ideas are welcome.

adgarland

no but good luck i have the same problem

Eddie 70

I don't remember what the exact solution to this problem was now. It has been a while since I fixed it but during all of that checking, I found out that there were electrical connectors reversed. One may have been the IACV and another one. There are two connectors close enough to each other that they can be plugged into the wrong sensor and cause the surging. When I corrected the mistake the car started running like it should have. It has been over a year since I was trouble shooting this and the car has ran flawlessly since discovering this and correcting it.

adgarland

thanks for the advise i will check it out.