Ok.

I have some queries about the BBM solenoid and how it functions..

I don't know which way is open and which is shut (or on/off) so I'll refer to it as activating, for when the solenoid starts sucking air through the line and pulls on the diaphragm.

As soon as my car starts the diaphragm activates and gets pulled.

And at 3800 it dose it's thing as normal and let's the diaphragm go.

But I thought the solenoid activated at 3800. I have a feeling mine is working backwards.

When I cross a multimeter between the 2 wires I have added for the solenoid I get a 0.06 volt reading.

Is this normal? And which way around do the wires go? I'm thinking I have maybe connected them backwards..

sounds right. the butterfly should be open when not running, its closes as soon as it starts up, then opens again at 3800 and above.

Yep, thought so..

I also did a test and at 3800 the solenoid gets a 12v feed.

Can you put a multimeter across the wires to the solenoid and see if you have a current as well?

As I mentioned I have it reading 0.06v when the car is all off.

Trying to narrow down an electrical drain.

I can watch my battery volts tick down with a multimeter when the battery is connected.
Also it drops 0.10 of a volt when I connect the battery too. IE: sitting at 12.65v then when I hook up positive it will drop to 12.55v. (for example of corse)

Should have connected the wires the same way as they were coloured in the plug... Red I think would have had constant power which tee's off the injector positive rail... Then the computer earths whatever the other colour wire is...

Wont matter which way you connect them, it will only work the same way... You would have to invert the computers signal to invert it's operation... Solenoid polarity says you should have connected them as you cut the plug off the car you got it from...

You are right... actuator closes at idle forcing air the long way around the manifold and then above 3800 it opens allowing the air to take the short cut...

how accurate is your multimeter? That .06V is bugger all and if you only have a $50 multimeter that could be an error reading?

What are you talking about the battery dropping .1V? Drops .1V when connected to what? The whole electrical system of the car vs completely disconnected?

Cheers,
Tim

Cool, ok.


I do have it wired as factory. I double checked and its all hooked up the same.

That operation description was what I needed too, now I understand which way it works, it's a lot less confusing..

Now with the battery..

Not too sure on the quality of the multimeter it's not a superschitt one tho, it's a decent looking older unit.

The battery volt drop in the last sentence I typed was 2 things.

First part was that when the battery is connected and just sitting there, switched off and the car keys in my pocket, I'll connect the multimeter, and it will come up with 12.xx volts...

And just standing there watching, the voltage ticks down slowly, I haven't timed it, but in around a minute it will drop about .04v.... About .01 every 20 seconds or so..

So by that I'm leaning towards a short somewhere.

Can't get the multimeter to read mili amp so I can directly see the draining current.

The second part was that when I disconnect the battery (take off positive) then put the meter across it will read 12.50v (for example) then just touching the positive terminal back on (decently of corse so it has a good connection) the volts drop to 12.40v (for example)

Then disconnecting the positive again will make the volts go up to 12.50v (for example)

I can't remember the exact amounts, hence all numbers being an example, but it was somewhere up to .5v difference..