Overheating, cooling system, trouble codes

1998 DODGE CARAVAN
235,000 MILES
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RAPHAEL SAWYER
  • MEMBER
  • 1 POST
My van listed above has a 3.8 liter 6 cylinder engine.
It is having a lot of issues with overheating and it has plenty of fluid and a new thermostat. Someone said that there could be trouble codes that keep it acting the same as before it was repaired. Also found 2 exploded spark plugs when mechanic was changing the plugs and wires. And alternator is good but loose I think.
Jun 9, 2021 at 7:30 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good afternoon,

Overheating is a mechanical issue. There are no codes for overheating. The only code that may come up is if the radiator cooling fans are not working. The cooling fan relay was a common failure for the fans if they are not working. I attached the location and a wiring diagram for you.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-an-electric-cooling-fan-works

https://www.2carpros.com/articles/engine-overheating-or-running-hot

I would start by having a leak-down test done on the cylinders one by one. You may have a damaged head gasket. The fact you have 2 bad plugs indicates there may be damage in those cylinders.

https://www.2carpros.com/articles/how-to-test-engine-compression

The other thing is the radiator. If it is clogged, it will cause this overheating. You need to have the radiator flow tested to see if it is clogged. I attached the procedure for replacing the radiator below.

https://www.2carpros.com/articles/how-to-replace-a-car-radiator

Roy

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Jun 9, 2021 at 8:52 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
I see you posted a response but nothing came through.

Can you send the reply again?

Roy
Jun 9, 2021 at 10:26 AM
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