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When I start my 92 Honda civic dx and it warms up it idles up and down what could cause this?

 
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It only surges during warmup?

 
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yes that is the only time

 
Rep Power: 234

Might have air in the cooling system, or a dirty IACV/throttlebody. Could be a vacuum leak but, usually that causes constant high idle.

 
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Thanks for your input,someone told me my idling sensor was going out.

 
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check your intake manifold gasket. spray with throttle body cleaner when its warming up. sometimes those get little leaks in them and once they warm up it seals it. if the leak is detected there it will be evident in your idle. your iac will not operate correctly if the gasket is leaky. hence once it warms up, your idle stops surging. this is just one of the things it could be. hope this helps.

 
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my 90 dx auto is surging bad too. but its all the time. changed plugs and wires, fuel filter and sprayed some carb cleaner in the carb. worked for a while then surges every now and then when i try to give it gas it boggs down??? any help

 
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I have the same car with the same problem. Idles high when first started cold. After warmup, idles up and down from 1000 to 3000rpm constantly. If you find a solution, let me know and I will do the same.

 
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try the idle air control valve or the fast idle thermo valve