ive noticed over the last couple days that when im driving my lights dim real low and i mean all my lights inside and out, when it does my speedo needle jumps. example- 50 to 80. also my cars fuel pump is possibly failing i do believe because i have about 12 psi but oddly enough it still runs(barely) i have to let it warm up for about 5 or more minutes and it still chugs when you go more than 1/4 throttle on it. any help at all would be great. also i have subs and amp but its been in the car for over a year.

its a 96 Z28 A4

 

How is your alternator? I dont think the speedo is the direct issue here but a result of low battery power.

DO NOT pull the battery cable while the car is running to test the alternator!! It will fry the alternator not test it. Also get your battery checked and tested as well as charged.

The low power can cause the fuel pump issues as well as the lights and speedo. Most auto part stores offer free testing of battery and alternators.

Massey

 

agree with massey, could just need battery terminals and cable ends wire brushed. check the power juction box (small red plastic box on the passenger fenderwell) and clean the wire ends there as well. check power/battery wires for any damage.

 

thanks guys i appreciate it.

 

sounds like the same problem i been having. i changed my battery guess ill get my alternator tested. i thought it was my spark plugs and wires.