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Amedee
Amedee, Dodge Technician
Category: Dodge
Satisfied Customers: 24775
Experience:  ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector
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2008 dodge caravan. Overheating on gh speeds or on a ghway.

Customer Question

2008 dodge caravan. Overheating on high speeds or on a highway. When I stop and wait it will go back to normal. Drives normal in traffic. Check engine codes are po300 po301 po303 and po138. And it shakes when I reverse
Submitted: 10 months ago.
Category: Dodge
Expert:  Amedee replied 10 months ago.

Hello and welcome! My name is ***** ***** I can assist you with your question. What size engine do you have?

Customer: replied 10 months ago.
3.3 l
Customer: replied 10 months ago.
I have replaced the thermostat
Expert:  Amedee replied 10 months ago.

Have you checked for a blown head gasket?

Customer: replied 10 months ago.
No. But I do not see any white smoke
Customer: replied 10 months ago.
you want me do a compression test?
Expert:  Amedee replied 10 months ago.

So do you know what is causing it to run rough?

Customer: replied 10 months ago.
I found on Google that high speed overheating could be because of a clogged exhaust manifold
Customer: replied 10 months ago.
I think they are bad spark plugs
Customer: replied 10 months ago.
Cylinder 1 and three
Expert:  Amedee replied 10 months ago.

Ok have you pressure checked the cooling system?

Customer: replied 10 months ago.
No?
Expert:  Amedee replied 10 months ago.

Well, I would at least start by ruling out any major stuff like a cracked cylinder head or a blown head gasket.

Customer: replied 10 months ago.
I will tomorrow
Expert:  Amedee replied 10 months ago.

If the converter was plugged up, it would prevent the engine from accellerating under a heavy load.

Expert:  Amedee replied 10 months ago.

You can remove the fron oxygen sensor to see if that will help but I dont think this is the problem. In addition, what are the chances that two or more spark plugs when bad at the same time? It is not very likley.

Expert:  Amedee replied 10 months ago.

The most common cause would be a blown head gasket, cooling fans not working or plugged radiator. I have seen plugged or restricted heater or coolant hoses so be sure to check those as well.

Customer: replied 10 months ago.
I replaced the radiator as well
Expert:  Amedee replied 10 months ago.

Ok, good. Then pressure checking the cooling system and running a block test or checking for HC's in the radiator would be a good things to do next as well.

Customer: replied 10 months ago.
While back I replaced cracked plastic t houses with metallic ones. Maybe they clogged up
Expert:  Amedee replied 10 months ago.

Anything is possible. It is worth checking into..

Customer: replied 10 months ago.
When I opened the radiot cap this morning there was a pressure, even through car was cool
Expert:  Amedee replied 10 months ago.

It will hold pressure for a while.. this is good. But this does not mean the head gaskets are good.

Customer: replied 10 months ago.
Do you do pressure test while engine is hot or cool
Expert:  Amedee replied 10 months ago.

With the engine cold and engine turned off.

Customer: replied 10 months ago.
I did it and it is holding it
Customer: replied 10 months ago.
10 min
Expert:  Amedee replied 10 months ago.

EXCELLENT!! This means there are no coolant leaks

Customer: replied 10 months ago.
May be I did not get the right thermostat
Expert:  Amedee replied 10 months ago.

I would get one from the dealership just to be sure. Then after installing it, be sure to bleed the cooling system (I am sure you did this when installing the last thermostat)

Expert:  Amedee replied 10 months ago.

I am glad I can help!

It has been a pleasure working with you. Please dont forget to honor your good faith deposit by rating my answer as "Excellent Service" for assisting you today.

Please let me know if you have any further questions.

Customer: replied 10 months ago.
Okey I will get one from the dealer
Expert:  Amedee replied 10 months ago.

Sounds good!

Customer: replied 10 months ago.
What is the best way to bleed the cooling system. I open the radiator cap and hit the exlrator several times
Expert:  Amedee replied 10 months ago.

With the engine cold, remove the radiator cap and start it up. Let it idle until it is up to operating temp. Then pick up the engine rpms to about 1500 for about 10 minutes or until the cooling fan comes on. Then install the cap and that should do the trick

Customer: replied 10 months ago.
Overheating problem solved but the codes keep coming back. What do you suggest I do
Expert:  Amedee replied 10 months ago.

Excellent! Glad to hear we got to the bottom of it! The misfire codes will need to be diagnosed and fixed. I would check the fuel system and ignition system first and go after the Po138 as that might be causing the misfire codes.

Customer: replied 10 months ago.
Po138 is oxygen sensor. Replace it?
Customer: replied 10 months ago.
How do I check the sensor
Customer: replied 10 months ago.
How do I check the ignition and the fuel system?
Expert:  Amedee replied 10 months ago.

You can check fuel pressure using a fuel pressure tester. One of the easiest ways to check the ignition system is to spray a light mist of water on the ignition components and see if the engine starts to run rough. If so, the tune up parts are bad and will need to be replaced.

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