1994 vette heater control head
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1994 vette heater control head
I changed the heater control head on my 94 vette. The numbers on the used module didn't match the old module. Changed module because control buttons weren't working well.
While driving it afterward entry pass key light came on. Then the door locks went crazy and and the interiors lights came on.
Also have H65 code in module 9 and active O2 sensor code for left bank.
Also got misfiring and coughing through the intake. Has new plugs, new plug wires, new opti spark and cap, Reman injectors, new mass air flow, new air filter, new fuel pump and filter and new fuel pressure regulator.
Is any of this related to changing the heater control module head?
I saw a U tube video about cleaning the control head contacts. I am considering trying this an re installing the old module.
While driving it afterward entry pass key light came on. Then the door locks went crazy and and the interiors lights came on.
Also have H65 code in module 9 and active O2 sensor code for left bank.
Also got misfiring and coughing through the intake. Has new plugs, new plug wires, new opti spark and cap, Reman injectors, new mass air flow, new air filter, new fuel pump and filter and new fuel pressure regulator.
Is any of this related to changing the heater control module head?
I saw a U tube video about cleaning the control head contacts. I am considering trying this an re installing the old module.
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The O2 sensors didn't code till after I changed the module.
But the coughing has been going on for a while.
I am at a loss on it. Its worse till it gets warmed up. Has throttle hesitation too. But once it come alive its gone. Almost seems like plug mis fire under a load. It has new Bosh double platinum plugs with multiple contacts to arc to.
I have new AC Delco plugs 41-908 been thinking about changing them.
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Thanks for the tip on adjusting door switches.
The O2 sensors didn't code till after I changed the module.
But the coughing has been going on for a while.
I am at a loss on it. Its worse till it gets warmed up. Has throttle hesitation too. But once it come alive its gone. Almost seems like plug mis fire under a load. It has new Bosh double platinum plugs with multiple contacts to arc to.
I have new AC Delco plugs 41-908 been thinking about changing them.
The O2 sensors didn't code till after I changed the module.
But the coughing has been going on for a while.
I am at a loss on it. Its worse till it gets warmed up. Has throttle hesitation too. But once it come alive its gone. Almost seems like plug mis fire under a load. It has new Bosh double platinum plugs with multiple contacts to arc to.
I have new AC Delco plugs 41-908 been thinking about changing them.
I stayed with the ac delco plugs.
Last edited by antfarmer2; Feb 8, 2016 at 08:11 PM.
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As far as I know they are the original AC Delco O2 sensors.
I can see the AC marking on the left one.
It had Nitrous run on it before I got it.
Car has 49,000 miles on it.
It has a 160 thermostat in it and fan comes on about 180 and doesn't shut off till temp falls below 170.
Which means it runs most of the time.
Does the ECM have a rev limit setting?
When you punch it open in at low speed it down shifts and tach hits the 6000 mark before it shifts. Seems to be nosing over before it shifts
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As far as I know they are the original AC Delco O2 sensors.
I can see the AC marking on the left one.
It had Nitrous run on it before I got it.
Car has 49,000 miles on it.
It has a 160 thermostat in it and fan comes on about 180 and doesn't shut off till temp falls below 170.
Which means it runs most of the time.
Does the ECM have a rev limit setting?
When you punch it open in at low speed it down shifts and tach hits the 6000 mark before it shifts. Seems to be nosing over before it shifts
I can see the AC marking on the left one.
It had Nitrous run on it before I got it.
Car has 49,000 miles on it.
It has a 160 thermostat in it and fan comes on about 180 and doesn't shut off till temp falls below 170.
Which means it runs most of the time.
Does the ECM have a rev limit setting?
When you punch it open in at low speed it down shifts and tach hits the 6000 mark before it shifts. Seems to be nosing over before it shifts
Change the front two o2's and hold on!!!!!! Might have someone look at your setting past my pay grade.
Last edited by antfarmer2; Feb 9, 2016 at 08:00 PM.
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Stock thermostat is supposed to be 180.
I know somebody changed fan settings and much more.
I need to get OBD 1 code reader with OBD 2 Plug or program tool to change some settings.
Anybody got any Ideas which one to get
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I have also learned that unplugging the primary cooling fan or the cruise control module wire will cause codes in module 9 on PCM.
Very surprised that anything on the engine being unplugged will code in module 9.
Figured all would code in module 4.
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Changed my O2 sensors no real change. Did clean and re install the heater control head. Works great now. Cleared my codes from module 9. Didn't recode after put the original heater control head back in.
I have also learned that unplugging the primary cooling fan or the cruise control module wire will cause codes in module 9 on PCM.
Very surprised that anything on the engine being unplugged will code in module 9.
Figured all would code in module 4.
I have also learned that unplugging the primary cooling fan or the cruise control module wire will cause codes in module 9 on PCM.
Very surprised that anything on the engine being unplugged will code in module 9.
Figured all would code in module 4.
Re installing original heater control stopped the problem I was having with passive keyless entry light on dash coming on, my door locks acting up while driving and interior lights coming on while driving.