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Amedee
Amedee, Dodge Technician
Category: Dodge
Satisfied Customers: 25656
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: 1 year ago.
Category: Dodge
Expert:  Amedee replied 1 year ago.

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

Customer: replied 1 year ago.
3.3 l
Customer: replied 1 year ago.
I have replaced the thermostat
Expert:  Amedee replied 1 year ago.

Have you checked for a blown head gasket?

Customer: replied 1 year ago.
No. But I do not see any white smoke
Customer: replied 1 year ago.
you want me do a compression test?
Expert:  Amedee replied 1 year ago.

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

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

Ok have you pressure checked the cooling system?

Customer: replied 1 year ago.
No?
Expert:  Amedee replied 1 year 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 1 year ago.
I will tomorrow
Expert:  Amedee replied 1 year ago.

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

Expert:  Amedee replied 1 year 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 1 year 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 1 year ago.
I replaced the radiator as well
Expert:  Amedee replied 1 year 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 1 year ago.
While back I replaced cracked plastic t houses with metallic ones. Maybe they clogged up
Expert:  Amedee replied 1 year ago.

Anything is possible. It is worth checking into..

Customer: replied 1 year ago.
When I opened the radiot cap this morning there was a pressure, even through car was cool
Expert:  Amedee replied 1 year ago.

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

Customer: replied 1 year ago.
Do you do pressure test while engine is hot or cool
Expert:  Amedee replied 1 year ago.

With the engine cold and engine turned off.

Customer: replied 1 year ago.
I did it and it is holding it
Customer: replied 1 year ago.
10 min
Expert:  Amedee replied 1 year ago.

EXCELLENT!! This means there are no coolant leaks

Customer: replied 1 year ago.
May be I did not get the right thermostat
Expert:  Amedee replied 1 year 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 1 year 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 1 year ago.
Okey I will get one from the dealer
Expert:  Amedee replied 1 year ago.

Sounds good!

Customer: replied 1 year 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 1 year 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 1 year ago.
Overheating problem solved but the codes keep coming back. What do you suggest I do
Expert:  Amedee replied 1 year 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 1 year ago.
Po138 is oxygen sensor. Replace it?
Customer: replied 1 year ago.
How do I check the sensor
Customer: replied 1 year ago.
How do I check the ignition and the fuel system?
Expert:  Amedee replied 1 year 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.