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Re: Ignition Switch Test ![]() Posted by Cmyles [Email] ![]() ![]() In Reply to: Re: Ignition Switch Test, BJensbass, Mon, 8 Jun 2020 08:40:38 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Quick test to distinguish a fuel problem from an ignition problem: Spray some carb cleaner through a vacuum port directly into the intake manifold and then quickly try to start engine. If it starts you have a fuel delivery problem. If it still won't start you have an ignition problem. Depending on a few details that test is about 95% reliable.
If a check valve fails or there is a small leak in the circuit causing fuel rail pressure to drop while parked that will cause long crank before start condition. Before starting the car you can check for pressurized fuel in the rail by cracking the banjo bolt at the front of the rail. If pressurized fuel sprays out that's a good sign. If fuel only dribbles out there's your problem. Nosmo King of course.
I have had ignition switches that dropped the run circuits while the start terminal was active and of course those cars were hard to start. Attach a test light or volt meter to the test socket in the fuse box. You want to use the pin socket that is closest to the inner fender or would be at 3 o'clock if the front of the car is 12 o'clock and the rear of the car is 6 o'clock (looking down on the test socket). That test terminal must be hot (12 volts) when the ignition switch is in run and start positions. Also, make sure that fuse #3 is secure, no fuse #3 = no ignition.
There are lots of multi-pin connectors in the EZK ignition system circuit and if one of them is unhappy you could get an intermittent staring problem. If that's the cause it will take some effort to locate.
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