Help with a 1992 buick?

Question

I have a 1992 buick 5.7 v 8 240,000 miles on it.I,ve replaced the thermostat coolent temp sensor temp sending unit. when i put the oem thermostat in it{195 degrees) the temp goes up and down. i put in a lowertemp thermostat ant it dose not get over 100 degrees no coolent loss. also no heat with the 160 thermostat I like the car to much any advise would be helpful Thanks

temp is stable with lower thermostat no electric fan fan works off clutch on water pump

i have not changed the water pump yet that is the next thing i m gonna try

np smoke from the pipesor any kind of sweet smell from burning coolent and its allways full car runs great just the temp problem

Answer 1

i own a repair shop,and it sounds like to me that it may have a stopped up radiator on it,,either that or the fins on the water pump are getting worn out bad, they don't circulate the water as good as they should,,the water pump wont leak any ,it just wont move the coolant through the engine as good as it should, i got one now that has over 200 k on it and it was running a little warm,i had to replace the water pump and the radiator in it to get it to cool down some but now its its fine,i have drove it for a few days to make sure before i give it back to the customer,,you may wind up having to change the pump,an flush it ut real good to get it to cool down some,good luck i hope this help,s.

Answer 2

I would say that you need to change t he water pump, the impeller is failing, that is a pretty easy change, you should always change the two at the same time, i don't think i would leave that 160 temp therma in there i would put a 180 with the new water pump and i think that your problems will go away.

Answer 3

restricted radiator, air pocket in cooling system caused by restricted radiator or restricted heater core or a blown head gasket all can cause your problem.
Also do not overlook a bad cooling fan motor and/or relay
If you turn on your A/C does your electric fan come on? Does the temp stay stable now?

Answer 4

try replacing the temp. control switch,temp fluxing up and down,should be on the side of the block,close to your thermostat

Answer 5

I would test the temp with a temp gun because I dont think it would go up&down like that a garge would probly test it for free. good luck NO heat is because it's not getting hot enought.

Answer 6

First examine the gas pump rigidity. If the rigidity is low, examine the gas clear out. If that's ok, that's probable the gas pump. If that's making a noisy noise, that's probable undesirable. wish this helps. carry close tech 40 yrs.