what makes the tbi injectors pulse? i have a steady spray at idle instead of a pulsing spray. it runs rich at idle. has new tune up, including distributer.

 

the ecm pulses the injectors via a ground signal. hook up a timing light and point it at the injectors while it is idling. it will look like a steady stream to the naked eye. is it throwing any codes?? are the injectors dripping at all. and replace the tbi gasket. when you do that turn the tbi over and clean the gunk out from underneath it.

 

Make sure your ignition timing is set right, if its retarded, the engine vacuum will be low causing the map sensor to tell the ecm to richen it up.

 

or a bad CTS (or disconnected CTS) will cause rich idle.

 

If the cts is unhooked it'll run rich all the time, the ecm will think the coolant is -40*.