97 2.2L overheat/fan not working

[Rolling7z]

Hello all, I am helping a friend with an overheating and fan not functioning issue. We replaced a faulty stuck thermostat, then within minutes of that fix the water pump went so we replaced that, the fan does not turn on when it is suppose to. We have tested the fan directly (working) tested the fuse (working) tested the relay (working) un-plugged the ECT sensor (fan turns on), jumpered ECT (fan turns on), tested the ECT sensor, (readings where all over the map so replaced it) But the fan still does not come on when it gets hot.

I have read that the 2.2l has two coolant sensors but there is not a sensor anywhere near the pulleys. Can anyone tell me what we should try/test next, or if you have a link handy to a similar situation can you post it please?

 

[melsg5]

what temperature are you letting the engine get to with the fan not coming on, have you had readings over 215-228 and no fan ?

 

[Rolling7z]

Yup there has been temperatures upto 250 before we shut it down

 

[melsg5]

the sensor that causes your fan to come on is located on the water outlet housing where the upper hose connects ? You do realize if nothing else is found it could be the ECM or the plug on the ECM.

http://www.autozone.com/autozone/re...olant-Temperature-Sensor/_/P-0900c1528003cddd

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[Rolling7z]

Yup I do, and i tested that sensor and it seemed faulty so I replaced it. I was thinking of the ECM possibility but if it was the ECM wouldnt the fan NOT turn on when the plug to the ECT was disconnected or jumpered?

 

[melsg5]

im puzzled why it turns on with both methods, unplug yes, jumped? guess you dont have access to a advanced scan tool like a Tech II?

 

[Rolling7z]

The only thing I have is a bluetooth elm327 and torque pro