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Wiring push button to fix hot start prob - Be Careful!! Posted by Gary Stottler [Email]  (#1463) [Profile/Gallery]
(more from Gary Stottler) on Tue, 12 May 2015 07:08:16
In Reply to: Re: fuel quality is very important, high ethanol levels, Name Left Blank, Fri, 8 May 2015 12:45:54 Members do not see ads below this line. - Help Keep This Site Online - Signup |
All,
Be very careful with wiring changes! Applying 12V to the Cold Start Injector may put you in a situation where pushing your button will cause the engine to crank, so probably best not to do it that way.
The Cold Start Injector is normally fired by 12V coming from the Starter (which is why you don't want to apply 12V to that line). This is the yellow wire to the Cold Start Injector. If you test that wire with a volt meter, you should have 12V (or so) there when the engine is being cranked. However, the CSI won't fire unless it also has a ground, which it gets through the Thermal Time Switch (screwed into the cylinder head between #2 and #3 intake manifold runners - should have yellow and green wires). The Thermal Time Switch only provides a ground when the engine is cold. So, in order to fire the Cold Start Injector when the engine is warm, you need to provide a ground circuit that is "made" when when you press your button. That way, you can control the Cold Start Injector when the engine is cranking without causing any other problems.
So, what you want to do is to splice a wire into the Green wire to the Cold Start Injector, run that wire to your push button (use a "normally open - momentary contact" switch that is only "on" while you are actively pushing the button) and then wire the other side of your push button to ground. Then when a) the starter is cranking, and, b)you pressing the button the Cold Start Injector will fire and you will get fuel into the engine to get it started. It will probably run roughly for a few seconds while the vapor is purged out of the fuel lines running to the injector.
I don't think it helps to run the fuel pump prior to cranking - the vapor is in the injector lines, so fuel pressure in the rest of the system does not help.
Hope that helps!
Gary
_______________________________________ Gary Stottler
, Wed, 6 May 2015 17:50:08, Thu, 7 May 2015 07:32:50, Tue, 12 May 2015 07:08:16 <-- Viewing This Message, Tue, 12 May 2015 07:15:58, Tue, 12 May 2015 06:43:48, Wed, 13 May 2015 05:35:24, Mon, 18 May 2015 16:17:53, Wed, 17 Jun 2015 05:47:23
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