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Discussion Starter #1
Last night I met Hidro to do some tests on our cars and I discovered somethings that I don't understand...


When I blow into the intake of the ISV the air passes trough and the Hidro ISV blocks the air passage... wich one is working correctly (I must say that the to ISV are diferent, mine is a BOSH unit and Hidro's is a VDO)

When we turn on the ignition my car make the ISV to work (mine make some vibration and Hidro's vibrates with very much high frequency that seems like there is a short-circuit in it) and Hidro's car only make the ISV work when the car is very cold. Any ideas on what is going on?

When we blow into a fuel line (I have tryed on the line that goes from the fuel distributor to the WUR or the cold start valve) should the air pass freely or should be some resistance. If there is some resistance could that be that that line is ?clogged?

thanks in advance

Felix Simoes
 

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Discussion Starter #2
I have cleaned the ISV with carb cleaner, up until the cleaner start coming out with the same color that it was going in...


When the engine is hot it idles to high +/- 1200rpms.
 

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one thing,really really strange...
my ISV was runing ok when i went for a drive.i touched the plug,and puff,she died!now my car doesn't idle properly in cold.it stays about 800 or less!
 

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<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><HR>Originally posted by HidRo:
one thing,really really strange...
my ISV was runing ok when i went for a drive.i touched the plug,and puff,she died!now my car doesn't idle properly in cold.it stays about 800 or less!
<HR></BLOCKQUOTE>

Check electrical continuity, and harness voltage.

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The ISV should buzz intermitently when the ignition is on, and the engine is not running. That said, I have heard of peoples cars not buzzing at all, but still working properly. Might want to check the continuty across the terminals, and the voltage at the harness, might be a fuse (#22 in case). You did mention that tey were two different systems though, so...?

Are the cars running/idleing correctly? If the tube was blocked/inoperative the idle should drop I believe.

You could always tear the ISV out, plug the hole in the intake, and throw a catch can/filter on the crankcase vent; then just turn up the idle a bit. It's a bitch in the cold though, I would try giving it a good cleaning if you think somethings up.

[ December 04, 2003: Message edited by: Josh Fryauff ]

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Discussion Starter #6
My engine is idling a litle high when it is hot (about 1200rpm) and I believe that is related to the fact that the ISV is not blocking completly the air, even with the idle adjustment screw all the way in.

One other funy thing is this:
- My car is a 1988 KR and the ISV cable connector has 2 pins and my ISV (that has been replaced from a friend's car that he was braking) has a 3 pins connector...

- Hydro's car is a 1986 KR and his ISV cable connector has 3 pins and his ISV (that is the same as my previous one) connector only has 2 pins.


when I did a test with Hidro's ISV on my car the idle speed droped to about 950-1000rpms (wich is correct) that is why I asked if some one new if all the ISV should block the air when are disconnected.

Don't tell me that I have to buy an ISV... they are so expensive and I haven't financialy recovered from the engine swap...
 

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Odd!

Could be a vaccum leak, or a bad o-ring in the idle adjustment screw.

Have you tried dsconecting the ISV while the car is running, and warmed? There is a way to adjust how much air bypasses the ISV while it's in the closed position. If you look inside one of the air inlets, you'll find a small allen head set screw (2mm allen wrench, IIRC). Adjusting this screw will increase/decrease the amount of air bypass you get when there is no power to the valve.

But from your description it just sounds like your ISV needs a good cleaning with carb cleaner (if your car is OK with ISV power disconnected). Especially since you saud that Hidro's ISV had your car running right. Try a good cleaning before messing with that set screw.

Maybe it is time for a new one!

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