Stumble on cold start..what to do? ...97 A4
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Stumble on cold start..what to do? ...97 A4
Never had a problem with smooth running on a cold start until I had headers installed last fall. I get a stumble in the first minute or two until enough heat builds up, then it runs fine. Am I running too rich or lean? I am sure it is related to the header install, but not sure what would cause it, although I had to have the 02 sensors edited out due to check engine light coming on immediately after the install. Should I go back to the shop that installed them (they also did the editing out), or what? I have heard the 97s run rich from the factory, so could that be aggravating fuel mixture now that my setup has been altered?
