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RedRkt01
09-29-2010, 04:09 AM
What would happen if I tried to run an VSV that is supposed to operate at 30-34 Ohms inlieu of the original VSV that operates at 38-43 Ohms? I have a pretty good reason to do this so I really need to know if it'll work. Unfortunately, I know next to nothing about electrical theory.

KooK
09-29-2010, 04:47 AM
Sorry but, what's a VSV?

RedRkt01
09-29-2010, 04:53 AM
Sorry but, what's a VSV?

Vaccuum switching valve. Completely non incident to whether you understand Ohms........

joe's gt
09-29-2010, 07:24 AM
As in, it wouldn't actuate at the correct point?:hsughno:

what is this for?

RedRkt01
09-29-2010, 02:29 PM
Is that what you'd happen? It's for the A/C Idle up VSV. The stock one uses smaller vaccuum hoses than my 3SGE uses. Soooooo I've gotta change out the VSV for the ST202 VSV. It should be the easiest, non-rigged solution. What do you think?

KooK
09-30-2010, 02:26 AM
Vaccuum switching valve. Completely non incident to whether you understand Ohms........

So what you're telling me is the application of an electrical unit has no effect on the type of power it requires? Such as something computer related that either reads 30 or 34 ohms (meaning on or off), something that reads between 30 to 34 ohms such as a pressure sensor (30 being zero psi and 34 being 100 psi), or a valve which could require between 30 and 34 ohms to shut, and the circuit breaks when it needs to open the valve.

Regardless, thanks for answering my question I suppose.

Now, ask yourself what adverse effect this particular unit would cause, what would happen if I put it in and it didn't work correctly? If damage to anything else is possible, I would probably either manipulate the signal to accept the new unit, or I would use the one that first came with the car. If there's no damage that can be caused by having this item malfunction, you're still faced with the question, I'm putting more resistance to this unit than what was intended, adverse effect could be signal strain causing either wire damage or the unit to rapidly switch back and forth, either destroying the unit or the wire (or fuse) going to it; or we're back to "I could modify the signal to factory specs for this unit, or replace it with the unit that came with the car."

Judging by the lack of response, I'm guessing you may be on your own here. You might be perfectly fine just attaching it right up, however I thought the same thing when I modified my lighting inside one of my cars to accept LEDs because nobody had replacement bulbs. I ended up burning a switch because of the strain I put by not decreasing power to the switch itself, just increased the resistance near each LED so I could keep stock bulbs in the gauge cluster itself (Just an example).

KoreanJoey
09-30-2010, 02:40 AM
Is there anything else on the VSV circuit? I doubt it'll hurt anything but with a low resistance the ECU "MAY" not recognize that the switch has been activated (don't know if that matters or not anyway).

joe's gt
09-30-2010, 05:19 AM
You could try it out. Won't harm anything, it just might not work as intended. If it does work fine, great!

RedRkt01
09-30-2010, 02:21 PM
I can't quite remember if anything else is on the circuit. I would think there would have to be; whatever the VSV influences downstream should be on the same circuit, right? It is for idle up so.....

I'll have to look at the wiring diagram.....that's about the only thing regarding electronics that I understand.

KoreanJoey
10-01-2010, 06:32 AM
No, the circuit doesn't need to have anything in it downstream. It could be one circuit telling the ECU that *hey it's time to add iac* and the ECU sends a signal to the VSV which goes click and adds more vacuum. Now... the only thing would be if the ECU is waiting for confirmation that the VSV has engaged (by giving a different engaged resistance), again, I don't know if the ECU checks for that, or even if it does, whether or not it'll actually do anything about it. Maybe throw a code or something.

RedRkt01
10-01-2010, 03:59 PM
I think Jeremy might be a good source of info here.

Luni
10-01-2010, 05:26 PM
Jeremy is like.. MIA

RedRkt01
10-01-2010, 05:37 PM
Pm'd him......was here 10 days ago.

alltracman78
10-05-2010, 01:23 AM
Jeremy is like.. MIA

I know. :( I have like no time; baby on the way, 11 hr work/commute days, trying to dig out from debt, ect. No more Marine bachelor life, I had to grow up and unfortunately that means I have very little time to devote to cars.

Cliffs;
To the original question, the VSV will be fine. The resistance of the VSV doesn't really matter [within reason of course].

Long version;
The AC VSV uses a 12 v input and the AC amplifier [AC ECU] switches the ground on and off. Honestly, in an OBDI, I don't think it even knows if it actually turns on and off. It won't effect the ECU because the load absorbs the amperage/voltage, all the ECU does is turn it on and off.
Even if it does monitor if it actually turns on/off, all it's going to do is look for 12v on the circuit from the VSV. It will look for 12v when the VSV is turned off, and when it turns it on it will look for 0v [or very close to it], because the load [VSV] is going to "absorb" the 12v. It's not going to look for a varying amount of voltage because it's a simple on/off circuit, not a variable input/output circuit.
Just for FYI, it does also have the AC pressure switch in the circuit, but all that does is when the pressure is too high or too low the switch opens and doesn't allow the 12v to reach the VSV [also splices off to the AC amplifier and is an input to the AC amplifier so if the pressure is too high or low the amplifier turns the AC compressor off].

I hope that makes sense. :/

RedRkt01
10-05-2010, 02:38 PM
Um.....Jeremy......that was the complete expert answer I was looking for. May Jesus welcome you personally in Heaven.

alltracman78
10-05-2010, 06:32 PM
Glad to be able to help. :)

RedRkt01
10-05-2010, 07:49 PM
As with anything, it could've gone either way. Alternatively, I could've said, "I award you no points and may God have mercy on your soul." ;)

But yeah....thanks that helped.