i have been having some trouble with my 94 z28 a4. you start it up and sometimes the check engine light will come on but untill it warms up its fine. once its to temp the light will go on and off in spirts but when you hit the throttle even a little it makes a loud clicking noise. i thought it was a injector (dry fireing) but i dont know. i looked for 3 hours in the forums and didnt find anything on this. would someone let me know whats going on and how to fix it. thanks lance

 

Exhaust leak?
Lifter tap?
Have you put it on a scanner to see what it's kickin' back? Autozone/Advance Auto will do it for free

 

i took the car to both of them and they told me they couldnt read a 94's codes. i took it to 4 different stores. it doesnt sound like a lifter tap or leak. its more of a clicking sound like something is trying to to open or close. when you press the gas 1/4 - 1/2 way it moves fine but you can hear a lound CLICK, CLICK, RADDLE, CLICK, then if you let up and then repress the gas it will do the same thing till a little after the check engine light goes out. then its fine. i didnt know if its an o2 sensor, or enjector? or what?

 

Ignition? Broken spring? Collapsed Lifter? Loose O2 Sensor? And I know the firestones around here have a OBD-1 reader so do the Quik Lube's