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Engine will not start. Floods.

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Old 06-20-2014 | 08:30 PM
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Default Engine will not start. Floods.

Trying to diagnose a no start issue with my 85.2. The fuel pump works perfectly, fuel is being delivered to the rail, I have spark, I have tach bounce and the compression is good. I put a noid light on the # 4 injector connector and it didn't light up when cranking. I have been searching and have not found anything yet that will help. I am looking for any input.

Last edited by mazdaverx7; 06-21-2014 at 12:04 AM.
Old 06-20-2014 | 09:22 PM
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Do you have power at the coil?
Old 06-20-2014 | 09:31 PM
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If it's just one injector, it's possible that your injector connector is defective or you might have a DME or DME connector issue.
Old 06-20-2014 | 09:55 PM
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I have good spark, so I believe there is power to the ignition coil.

I rechecked with a different noid light and I get to light up on each injector connector, but the noid light is dim with each pulse.
Old 06-20-2014 | 10:06 PM
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I verified that each injector clicks operates by applying 12V directly to each injector and manually pulsing each one and I heard a click with each application of power.
Old 06-20-2014 | 10:22 PM
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Here's short video of the engine cranking, verifying injector pulse:

http://s246.photobucket.com/user/maz...11857.mp4.html
Old 06-20-2014 | 10:28 PM
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One short video of the tach bounce that I have:

http://s246.photobucket.com/user/maz...12340.mp4.html
Old 06-20-2014 | 11:09 PM
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Ok, i am getting fuel to the engine but the plugs are fouling every time I crank it. I am getting good spark, verified on each cylinder. I wonder if its not getting the correct amount of intake air.
Old 06-20-2014 | 11:24 PM
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You have fuel and spark, so air is logical (if unlikely). You could check TPS and AFM. I would do compression and leakdown too.
Old 06-20-2014 | 11:32 PM
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I did a compression test and it was good, within 5 or so psi on each cylinder and all were at or over 140psi
Old 06-20-2014 | 11:42 PM
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Hmm. Crank position sensor maybe?

<edit> no, that would connotate no spark.
Old 06-21-2014 | 12:14 AM
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Have you done any other work lately?
Old 06-21-2014 | 01:05 AM
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Has this car ever run under your stewardship? If so, what were the last maintenance items you addressed?


Originally Posted by mazdaverx7
...fuel is being delivered to the rail, I have spark...
Fuel to the rail does not ensure a running motor. Have you pulled the rail [with injectors connected] and verified fuel spray, while cranking, at each injector?

You have spark...where? At the coil, at the distributor, or at each plug terminal?


Originally Posted by mazdaverx7
i am getting fuel to the engine but the plugs are fouling every time I crank it.
What does this mean? When you pull the plugs after cranking the motor, they come out black covered in oil/carbon/soot?
Old 06-21-2014 | 02:19 AM
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I have verified a bad reference sensor...

The car has never run under my ownership. I bought it non running. I pulled the rail and cleaned the injectors and replaced the o-rings and pintle caps. I pulsed each injector with 12V and verified that each one worked.

I have spark at each plug when cranking the engine.

When I crank the engine and then pull the plugs they are wet with gas.
Old 06-21-2014 | 04:33 AM
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Edit- never mind....


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