Intermittent no Start

1979 DODGE VAN
86,000 MILES • 5.9L • V8 • RWD • AUTOMATIC
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KRISTA EXNER
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Okay so bare with me so I can list everything for you. Last year van started backfiring while driving down the road and it quit running one day and would not start again. I replaced the dual ballast resistor, coil, plugs, wires, cap, rotor, starter relay and final found it to be the ignition module/spark controller.

Two months later the van would occasionally shut off and not start sometimes. Stored it for the winter and brought it out two weeks ago to it running fine! No issues.

Last week I filled up with gas and parked in the driveway. Went out in the morning to start it and would not fire! Turns over strong but will not fire at all!

Looks like I have spark. Checked coil with a known good one just in case and no change. Tried jumping power to coil no change. Checked pickup coil and ohm tests are good. Cleaned all grounds. Rebuilt carburetor thinking maybe a fuel problem but has fuel too.

Left it a day and came back to it and it fired first turn of the key! Tried three more times In a row and it is good. Left it for an hour came back and would not start again.

Lost for what to do next!
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Apr 24, 2017 at 1:49 PM
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HMAC300
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then if the pick up is good, and resistor new then it is probably the control unit on firewall or poor connection or see if you get good spark from coil to dist if you are spray carburetor cleaner down carburetor see if it fires if it does then it is a fuel problem like maybe the float level is to low, accelerator pump etc. you can test fuel by doing the 1/2 pint in thirty seconds velocity as well. one other thing Chrysler always had a filter prior to pump see if it is clogged.
Apr 25, 2017 at 5:01 AM
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KRISTA EXNER
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Hi as mentioned above the control unit is also new, I am getting spark. Carburetor has been rebuilt. Filter changed. Carburetor cleaner caused a backfire so loud the pressure destroyed my new muffler.
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Apr 25, 2017 at 5:10 AM
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STRAILER
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Hello,

When the engine does not start can you check for power at the coil, it sounds like the ignition switch has gone bad which will cause the intermittent starting which will blow up the muffler as well. I am seeing a starter relay that supplies power to the coil as well, here is a guide and a wiring diagram so you can do some checking when the engine does not start.

The ignitions switch is the "electric control" in the diagram

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please run some tests and get back to us so we can continue helping you.

Cheers, Ken



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Apr 25, 2017 at 11:26 AM
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KRISTA EXNER
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Hi trying to figure out how an ignition switch has anything to do with my muffler? Also as stated above the muffler blew up from a backfire caused by the dude above telling me to spray carb clean into the carb.

Power at the coil is 6 volts in "run" position and 12 volts during cranking. (Normal for a dual ballast resistor setup) engine cranks fine just does not fire. Ignition module is new, starter relay is new, ignition is good (as stated above)
Apr 25, 2017 at 1:08 PM
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HMAC300
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check the timing on timing chain/dist. these things had plastic timing gear on cam and would jump or the gear would shatter and it would still run but run like crap. they sold start sometimes and other times not but after repeated start attempts would jump back enough to run although it normally ran like crap.. low compression on all cylinders as well as timing marks not lining up dist to balancer would be a good indicator. I doubt the carb cleaner caused the backfire unless you sprayed a whole can into the engine.
Apr 25, 2017 at 11:21 PM
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KRISTA EXNER
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Vehicle never backfired until I used that carb cleaner.... when vehicle starts it runs perfect. When it doesn't it just turns over forever. Does not sound like timing is the issue.
Apr 27, 2017 at 7:32 AM
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HMAC300
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then recheck the carb its either the float level to low, needle/seat stuck or float level to high and pouring gas into it when off. also could be a choke problem when hot by being closed. what are compression readings on all cylinders?
Apr 27, 2017 at 8:52 AM
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KRISTA EXNER
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Manual choke.. Compression wouldn't be an intermittent issue. The float is set properly. Can not safety view the timing marks unless I remove the power steering pump. This site is not helping. Thanks anyways I'll continue working on it alone
Apr 28, 2017 at 5:12 AM
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STRAILER
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We are sorry if we are upsetting you.

If the ignition switch is shorting when it gets warm it will intermittently shut off which then fills the muffler with fuel then the ignition switch starts working again it ignites the fuel in the muffler which make the do that.

Most of the vans that year had a auto choke so we apologize for that.

When the van stops running can you please check the brown and white wire coming out of the ignition switch for power?

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester


Please let us know what happens.

Cheers, Ken
Apr 29, 2017 at 4:39 AM
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