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Q: 1979 GMC Van is overheating

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We drive a '79 GMC Van and it's heating up like crazy. We had recent oil changes, transmission serviced, radiator flushed. We had the radiator cap changed, thermostat checked and all the fluid levels are good. Any idea what could be bad?

I have a video "How to Fix an Overheating Car". You should watch it because it has to be one of those things that make it overheat. The only other thing it could be is if your catalytic converter is clogged up. It will make the engine overheat but for that you can get it tested. Any good mechanic can place pressure gauges on before and after to test and see if there’s a bunch of pressure before the catalytic converter, like 8 or 10 PSI, and if there is hardly any after. If so, the catalytic converter is clogged up causing the car to overheat.

As I mentioned before, try all of the tests in my video. It’s got to be one of those issues or a clogged catalytic converter. Also, I’d recommend having a certified mechanic take a look at your car to diagnose and fix your overheating problem if it persists.

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