Car has an annoying and persistent overheating issue?

FYREFAERYE

MEMBER
2002 CHEVROLET CAVALIER
2.2L
4 CYL
RWD
AUTOMATIC
205,000 MILES

My car has an annoying and persistent overheating issue. Normal driving conditions in motion it stays just above 195. When sitting at long red lights it tends to go to the next peg. I've changed the thermostat, reservoir cap, coolant temp sensor, fan and fan relay. I think that's all. It all starts to blur together after a time. No visible leaks that I have found, no oil in the coolant or vice versa. Oh and I can't drive it over 65-70. Any speed beyond that and it blows coolant. System has been burped multiple times using a burp funnel and I make sure the coolant is 50/50 mixed. Oh and turning on heat only causes it to overheat faster. I'm at a complete loss. I've worked in parts for 7 years and nothing I can come up with or any tech acquaintances has helped at all.

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

An engine can overheat due to a number of reasons.

You could have a faulty water pump that is not circulating the coolant properly. Which will cause the engine to overheat.

https://www.2carpros.com/articles/symptoms-of-a-bad-water-pump

Also, it could be due to excessive restriction or blockage in the cooling system.

Have you tried to flush the cooling system?

Also, the overheating can be due to a bad radiator.

https://www.2carpros.com/articles/how-a-radiator-works

You mentioned that you have replaced the fan and the relay. So, does the fan operate when it is supposed to?
If there are wiring issues the fan will not operate regardless of the fan motor or the relay.

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.

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