Mechanic says the secondary is not coming on because the ecm won't ground out. It needs to be replaced. Anyone know better or is he completely right?

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87 Iroc-z Black out/Grey in. 350 tuned port. Auto. T-tops.
#3 Earnhardt is #1!!

 

hmm, i don't know so much about ur ECM, but might wanna check that temp sensor on the drivers side of the block under the exhaust manifold, that is what controls the secondary fan as far as high temp. take the wire off, ground it on something good, and see if that causes it to come on, im pretty sure thats how to test it, i think..

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- David
88' GTA 5.7L TPI MODS---> air foil, K&N, Shift Kit, 180* therm, TB bypass, Gutted CAT, Flowmaster 80 Series

http://www.geocities.com/david_angel_16

 

Most secondary fans are not controlled by the ECM. You need to do as the above post suggests...ground the wire that is going the the temperature snap switch in the passenger side head to a ground. The fan should activate (key must be "ON"). If the fan does not activate, either the relay or the motor itself is bad.

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Mike Metzler (Desert86Roc)[*] Check Out:SpeedWorldMotorplex.com[*] Check Out:Chevrolet F-Body Online Part & Illustration Manual[*] www.MetzlerRacing.com

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