mdoherty53

I call it the bypass circuit because it is bypassing the thermostat Might not be the right term but if the flow through the heater is not strong enough it will affect the opening of the thermostat That much I am sure about .Michael It took us months to find the problem but the give away was that the hot return from the heater feeds directly on to the thermostat and these things rarely are not there for a purpose .when we had replaced everything in the cooling system and it still overheated we finally found the link I just think it is worth checking for .M

Those symptoms sound very like my 94 and if it will run OK without a thermostat it is probably worth trying a shunt across the heater If if is a blockage in the core it could stop the thermostat from opening and overheat badly and can be mistaken for HG

These cars are getting old now and I 'll tell you if the heater core bypass check is not included you could be wasting a lot of money.If the thermostat is not opening and most of the air is out of the system and thermostat checks OK that is what it will be If anyone is skeptical just try clamping a heater hose and see how long it takes for the fans to stay on

Some of you will be surprised but I had a problem with a 94 2.2 thermostat not opening properlyand sometimes not at all and it turned out to be a slight blockage in the heater core I think it is a rare occurance but in this case the slowness of the hot water returning to the pump<thermostat>caused cavitation around the thermostat and hence it did not open Cure -Try bypassing the heater and if it is better you can fit a small permanent bypass without the need to replace the core True Michael

I was planning to do that myself but was hoping to slip the sender into the hose or maybe put a fitting in the top hose to fit the sender to I just found out that these temp gauges stay the same from about 160 to 205 deg f what are others experiences and temp readings Michael