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I have a 1998 dodge intrepid…. 85k miles… 3 days ago it started to run hot….
PLENTY of coolant… I thought thermostat at first… So i checked the upper and lower hose… Upper house is getting WAY hotter than the bottom.. and it has pressure on it…. So that tells me the thermostat isnt locked up…. But i also noticed it only gets under TIGHT pressure once it runs hot… … i cant feel liquid flowing through it.. but it gets hot and under pressue…. My fans are turning on and working right…. the 2 things i narrowed it down to are water pump or head gasket… butno signs of a head gasket… at this point im stuck… any advice???
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I just wanted to add. If you don’t have the tool to test the pressure in the cooling system, you can rent one at any Advance Auto Parts. The way it works is you pay the full price of the tool then you return it and get a 100% refund back on the tool. So your not spending any extra money on something you might only use just once.
My friend thought his head gasket was the reason his civic was over heating. He was sure it was and he was ready to shoot his car but when I went over to check it out I told him to turn the car on and while up front not only did I notice some electrical repairs, I also felt that the fan was blowing towards me so that’s when the investigation questions began. He claimed someone had replaced the fan switch and cut the wires. So when they put it back, they installed the wires backwards so pretty much it gave him a sigh of relief when I told him to test drive it after I hooked it up right…
Maybe check your oil to see if any bubbles ,also check radiator for debris and any coolant leak indications, also if all checks out maybe you need to bleed cooling system…but i would suggest getting it pressure tested first after visual inspection…
There seem to be a lot of votes for a head gasket, but I’ll put a vote for it being a water pump impeller failure, or perhaps air trapping. I don’t disagree with any of the suggestions to pressure test the system or do a leak down test. However I would use one of those testers that check for exhaust gas inside the rad, and if that were negative I would not consider a head gasket failure to be likely. I would also take the radiator cap off, fill it to the point that you see water in the rad, and then run the engine for a few minutes with rad cap off. Can you see water moving inside the rad, after it heats up to open the thermostat?
With the mileage you have on the engine, a water pump could have easily failed.
I made a video to address this very issue that has some checks and how to perform them, don’t assume test and confirm. BTW the top hose is the feed hose that carries hot water from the engine to the radiator to be cooled, the lower hose carries the cool water back to the engine however if the lower hose doesn’t warm up a little then I might suspect a thermostat issue. Here is a link to the video.
Yes you will need to bleed the cooling system real good.
I will not do anything to a cooling system without bleeding it after.Ok Well.. today i replaced the thermostat…. It eventually over heated again…. although it took a bit longer… it over heats while sitting and driving…..
would i need to bleed the system if i just swapped out the thermostat??? so what should my next step be??? and where is the bleeder screw anywaysIf its over heating while driving, turn the blower motor on full speed with high heat. If the temperature drops, you may have a failing water pump. The impellers on the pumps if there metal will fail over time due to electrolysis.
Did you pressure test the radiator cap too?
Do you notice if your cooling fans engage at idle?
And did you follow every ones advice on pressure testing the system?
A lot of engines don’t have bleeder screws, so for those you just run the engine with rad cap off, waiting for the thermostat to open and release trapped air back to the rad. Keep filling through the rad cap until it won’t take any more — Leak free funnels work well for that. Of course that technique relies on the water pump to move trapped air back to the rad, so if your water pump is bad it may not bleed very well.
Quoted From 2StrongMNG:
Ok Well.. today i replaced the thermostat…. It eventually over heated again…. although it took a bit longer… it over heats while sitting and driving…..
would i need to bleed the system if i just swapped out the thermostat??? so what should my next step be??? and where is the bleeder screw anywaysFirst question, why? If you follow the steps in the video link I sent you on Diagnosing an Overheat it should lead you to some reasonable conclusion about the cause of the overheat. Aftermarket thermostats for Honda’s are not that great and considering how important engine temperature is to the fuel injection system I think it’s critical to use the correct parts so if you took out an OE t-stat and put an aftermarket in I think you took a step backward. ANYTIME you open the cooling system you need to bleed the air out especially in a Honda. Lastly the bleeder valve is only there to help you fill the system faster, bleeder valve or not follow the procedure in the Bleeding a cooling system video and you will get the air out of the system and eliminate that is the cause of the overheat. Once again here are the links to bleeding the cooling system and diagnosing an overheat.
http://www.youtube.com/watch?v=zUpXgAJ1 … ure=relmfu
http://www.youtube.com/watch?v=hUzOTnsW … ure=relmfu
iv watched the video 3 times… iv done those steps…… and where are you getting honda from?? the title of the add is 1998 dodge intrepid
The other thing to watch out for is some t-stats have a specific way they need to be installed – there’s a hole or small valve that needs to be in the right orientation. Not all cars have them, but if you do and it’s installed wrong that may give you grief when bleeding.
Quoted From 2StrongMNG:
iv watched the video 3 times… iv done those steps…… and where are you getting honda from?? the title of the add is 1998 dodge intrepid
Oops sorry bout that. My point is that if you check the system for leaks with a pressure tester, check for air in the system, check the cooling fan operation, and check for a combustion leak that pretty much covers the bases as far as finding a cooling system problem. At least one of those things is the cause. It’s a remote possibility that the water pump is also having issue and not moving coolant as it should, the idea is to eliminate the other causes first as the only way to verify a bad water pump is to remove it and inspect it.
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