My 87 will not start
Thread Starter
Heel & Toe
Joined: Jan 2015
Posts: 17
Likes: 0
My 87 will not start
It started out as an intermittent problem but now it's permanent. Turn the key and nothing. Started out by jumping the starter with key in the on position and she cranks. Bypassed the vats system...still nothing. Jumped the starter enabler relay..nothing. Jumped the neutral safety switch just to eliminate as a possibility...nothing. Would love any input.
Oil Producer
Joined: Apr 2014
Posts: 9,368
Likes: 2,735
im subbed for solution.
i THINK i recall reading once that the ecm looks for signal back from the dizzy and if it doesn't get it, it won't start? Something about a bad coil and measuring the voltage into and out of the dizzy to see if juice is making it back to ecm while cranking. but...don't go on a wild goose chase based on these comments. somebody like Cliff should chime in.
Do you have the service manual? PM me.
i THINK i recall reading once that the ecm looks for signal back from the dizzy and if it doesn't get it, it won't start? Something about a bad coil and measuring the voltage into and out of the dizzy to see if juice is making it back to ecm while cranking. but...don't go on a wild goose chase based on these comments. somebody like Cliff should chime in.
Do you have the service manual? PM me.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The VATS module enables the starter relay when it sees the correct key pellet resistance. You should be able to hear the starter enable relay clicking when you turn the ignition to the start position. It lis located behind the DIC in the center cluster.
The VATS module sends a 30 Hz square wave to the ECM. When the ECM sees that signal it enables the injectors. The ECM uses distributor reference pulses from the ignition module to synchronize the firing of the injectors to the rotation of the engine.
It sounds like your problem is in the starter enable system and you already looked at the obvious things. I suggest poking around with a voltmeter or test light to make sure the voltages are getting to where they ought to be going.
The VATS module sends a 30 Hz square wave to the ECM. When the ECM sees that signal it enables the injectors. The ECM uses distributor reference pulses from the ignition module to synchronize the firing of the injectors to the rotation of the engine.
It sounds like your problem is in the starter enable system and you already looked at the obvious things. I suggest poking around with a voltmeter or test light to make sure the voltages are getting to where they ought to be going.
