Question about 1994 GMC Sonoma

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Why is there no coolant flow in my radiator

Just put in a new thermostat, there seems to be little or no flow in rad with cap off

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  • GMC Master
  • 975 Answers

Won't be till the stat opens ,pretty cold out ,The stat is almost boiling temp.195 degrees.Not sure what the problem is but if it's getting hot or something,just take the stat out and watch the flow then.

Posted on Mar 19, 2014

  • Geoffrey White
    Geoffrey White Mar 19, 2014

    Hate to say it, but thermostats are sometimes installed upside down. They key question is: does it overheat now?



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Posted on Jan 02, 2017

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SOURCE: radiator cap came off and lost alot of coolant.

Cap cannot come off unless it was left loose. (most are a bit difficult even when removing on purpose) Refill with 50/50 mix right into the radiator while running, then re-fill bottle after closing cap. As always, don't open cap when radiator is hot.

Posted on Jul 11, 2009

  • 1201 Answers

SOURCE: I have a 2001 sonoma which is running high on

The radiator might be clogged. Take it and have the system flushed out,and back flushed, that will tell if there is a clog somewhere. If the radiator is too clogged, it will need to be replaced.

Posted on Mar 28, 2010

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SOURCE: engine is running hot .light comes on and will

Yes,it could be...Try replacing your thermostat.

Posted on Oct 19, 2010

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SOURCE: 97 jimmy has poor heat,fan works,changed

i had a 95 blazer with ice cold heater i just backed flushed the heater core and it work like new, all you gotta do is find the 2 hoses going to the firewall and disconnect them from the motor and using a garden hose run water through 1 and see if you get some crud out of it.

Posted on Dec 15, 2010

  • 14 Answers

SOURCE: Loosing small amount of coolant

Check your manifold(upper plenum) area. A leak in the gaskets is common in GM cars. heater fittings where leaking bad in my 2000 impala and now I have to replace those gaskets. The best recommendation I can give you if you wanna save money is get a Tech like myself not working for a company who rewards them for selling parts, and they should be able to find the direct leak(s) and not just guess.
I would start with a simple coolant leak detecting dye Kit.

Posted on Dec 16, 2010

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