Chevrolet Repair: 1997 Chevy Tahoe, chevy tahoe, distributer

Question
Hey wayne!!
We finally installed the new distributer, the check engine light went off, and now it is back on. the tahoe is running rough, rough idle. Any ideas on what it is now? We had a friend install the distributer, he knows a little about cars, my bf thinks it has to do with the timing, but my friend says it is automatic timing, i dont know what it is, U have been a savor! Atleast the thing is back on the road, but its eating up a lot of gas, and not running right. Please if you have any advise...

Answer
Hey,

 Its very important that the ignition timing is set properly or it will set a crank/cam synch code as soon as you drive it.  It does have automatic timing but that is based on the base timing being set correctly.  There is a plug under the dash by the glove box that needs to be disconnected.  Its called the EST connector and shuts the computers ability to adjust ignition timing.  
 Turn vehicle off, disconnect set timing connector, start vehicle and run to operating temperature.  Set timing to spec, I usually set it to 2 degrees after TDC.  Turn vehicle off and reconnect set timing connector.  Start and run.
 If the timing wasnt set with a gun then it isn't going to run worth a pinch of coon crap.  The computer can only control timing properly when it assumes base is correct.  If base was set incorrectly at 15 degrees than all adjustments would be x plus 15 degrees and it isn't correct.

w

Wayne