No spark or check engine light
Professional
Joined: Aug 2010
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From: San Angelo, Texas
Professional
Joined: Aug 2010
Posts: 242
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From: San Angelo, Texas
Well you almost replaced the entire ignition system but I dont recall you saying anything about the Ignition Coil that would be seperate from the distributor nor do I see that you checked the Distributor Gear to make sure it isnt broken/cracked.
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Joined: Aug 2008
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From: NC
Isn't the ignition phase after the PCM turns on, though?
Therefore if he isn't getting a check engine light (aka the PCM isn't powering on), it's not going to allow power to be sent to the ignition coil?
I don't have the schematic in front of me, but I seem to recall troubleshooting no spark at the ignitor coil before reaching the PCM as we backed up in the whole starting sequence.
I guess what I'm saying is that if there were anything wrong with his ignition circuit, that would largely be controlled by the PCM (but directly powered off the battery, I know), and therefore he should still have his PCM power on, relays click, and the CEL at least flash to test.
Therefore if he isn't getting a check engine light (aka the PCM isn't powering on), it's not going to allow power to be sent to the ignition coil?
I don't have the schematic in front of me, but I seem to recall troubleshooting no spark at the ignitor coil before reaching the PCM as we backed up in the whole starting sequence.
I guess what I'm saying is that if there were anything wrong with his ignition circuit, that would largely be controlled by the PCM (but directly powered off the battery, I know), and therefore he should still have his PCM power on, relays click, and the CEL at least flash to test.
Professional
Joined: Aug 2010
Posts: 242
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From: San Angelo, Texas
Isn't the ignition phase after the PCM turns on, though?
Therefore if he isn't getting a check engine light (aka the PCM isn't powering on), it's not going to allow power to be sent to the ignition coil?
I don't have the schematic in front of me, but I seem to recall troubleshooting no spark at the ignitor coil before reaching the PCM as we backed up in the whole starting sequence.
I guess what I'm saying is that if there were anything wrong with his ignition circuit, that would largely be controlled by the PCM (but directly powered off the battery, I know), and therefore he should still have his PCM power on, relays click, and the CEL at least flash to test.
Therefore if he isn't getting a check engine light (aka the PCM isn't powering on), it's not going to allow power to be sent to the ignition coil?
I don't have the schematic in front of me, but I seem to recall troubleshooting no spark at the ignitor coil before reaching the PCM as we backed up in the whole starting sequence.
I guess what I'm saying is that if there were anything wrong with his ignition circuit, that would largely be controlled by the PCM (but directly powered off the battery, I know), and therefore he should still have his PCM power on, relays click, and the CEL at least flash to test.
I am still thinking it is the coil or ignition switch that is what I would think to check. My .02
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Captain
Joined: Oct 2006
Posts: 565
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From: De Soto KS
Yes, I used the shop manual and checked it with my multimeter. Then gave it to my dad and had him test it. Then took the coil to Auto Zone and all three confirmed that the readings were with in spec.
Yes, I checked that the check engine light wasnt burned out by placing a jumper from the battery into pin 32 I believe which is the check engine light. Once the jumper was in place I checked the dash and sure enough, it was working.
I tried to do all my testing from the wiring harness. So that I could see what the computer was getting / not getting.
Yes, I checked that the check engine light wasnt burned out by placing a jumper from the battery into pin 32 I believe which is the check engine light. Once the jumper was in place I checked the dash and sure enough, it was working.
I tried to do all my testing from the wiring harness. So that I could see what the computer was getting / not getting.
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Captain
Joined: Oct 2006
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From: De Soto KS
You are correct that is why I was wondering if he checked the coil. If the engine has no spark, check for voltage at the coil positive terminal when the ignition key is on. If there is voltage, the problem is on the trigger side of the coil "pickup, crank sensor, ignition module or primary wiring circuit, however you replaced most of this already so dont think this is it". If there is no voltage at the coil, the problem is on the supply side "the ignition switch or ignition wiring circuit".
I am still thinking it is the coil or ignition switch that is what I would think to check. My .02
I am still thinking it is the coil or ignition switch that is what I would think to check. My .02
After looking at the schematics I am seeing on page 8w-30-21 that the ignition coil two leads are #1 ASD Output and #2 is ignition coil #1 driver. Lead #1 comes from the PCM and thus is the way in which the PCM tells the coil when to fire. I am also assuming that the PCM has to collect information from other various components to calculate when to fire that ignition coil. So if the PCM is dead then it wont be receiving any signal. If it is receiving a signal then the PCM is good and that is why you are saying that there must be another faulted ignition component or wiring some where.
Sorry if I am over analyzing this, just trying to make sure that I am on the same page with everyone else.
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Captain
Joined: Oct 2006
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From: De Soto KS
Ok, Just checked the #1 lead to the Coil. From off to ignition switch on, it went from .000v to .001v then back to .000v I then tried cranking the engine. And while cranking, it jumped around a lot, at first got a reading around .2v then it settled around .158v
Does anybody know what it should be reading at this time? I would think that it would read a lot higher?
Does anybody know what it should be reading at this time? I would think that it would read a lot higher?
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Captain
Joined: Oct 2006
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From: De Soto KS
OK I think I answered my own question. Found this on page 8D-10 of the shop maunal.
(3) Attach one lead of a voltmeter to the positive
(12 volt) jumper wire. Attach the negative side of
voltmeter to a good ground. Determine that sufficient
battery voltage (12.4 volts) is present for the starting
and ignition systems.
(4) Crank the engine for 5 seconds while monitoring
the voltage at the coil positive terminal:
² If the voltage remains near zero during the entire
period of cranking, refer to On-Board Diagnostics in
Group 14, Fuel Systems. Check the powertrain control
module and auto shutdown relay.
² If voltage is at or near battery voltage and drops
to zero after 1-2 seconds of cranking, check the powertrain
control module circuit. Refer to On-Board Diagnostics
in Group 14, Fuel Systems.
² If voltage remains at or near battery voltage during
the entire 5 seconds, turn the key off. Remove
the 60-way connector (Fig. 13) from the powertrain
control module (PCM). Check 60-way connector for
any spread terminals.
(3) Attach one lead of a voltmeter to the positive
(12 volt) jumper wire. Attach the negative side of
voltmeter to a good ground. Determine that sufficient
battery voltage (12.4 volts) is present for the starting
and ignition systems.
(4) Crank the engine for 5 seconds while monitoring
the voltage at the coil positive terminal:
² If the voltage remains near zero during the entire
period of cranking, refer to On-Board Diagnostics in
Group 14, Fuel Systems. Check the powertrain control
module and auto shutdown relay.
² If voltage is at or near battery voltage and drops
to zero after 1-2 seconds of cranking, check the powertrain
control module circuit. Refer to On-Board Diagnostics
in Group 14, Fuel Systems.
² If voltage remains at or near battery voltage during
the entire 5 seconds, turn the key off. Remove
the 60-way connector (Fig. 13) from the powertrain
control module (PCM). Check 60-way connector for
any spread terminals.