Ok its a stock EL ghia sound system aside from four pioneer speakers, the problem si this when ever i listen to a cd the left hand side front speaker and rear speaker dont work but switch it to the radio and all work fine. Some times when on cd mode the speakers will drop in and out but most of the time they just dont work, ive check all connections to the amp and to the speakers and all are ok. cna any one surgest something?

Michael

Is this the premium system? Is it the left at the rear that is playing up as well as the front? But only on cd correct?
I would suggest the fault would be in either cd stacker or stacker cable. Easiest way is to try another stacker if you can and see if the fault is still there. Otherwise if you can get hold of a diagram for the pinouts to see which wire is for the left audio signal from the stacker to headunit and check for continuity while moving the cable at each end to see if you can replicate the fault, if this is the case just replace the wire.
Somone on here may have the diagram that you need....
Cheers, Outlawxr6...

I had this EXACT problem when I bought my fairmont, it was an el-cheapo aftermarket headunit that I got with it, but exactly the same fault as you seem to have...

I never did figure out why it was doing it, but upon replacing the headunit everything worked A-OK, which was a partial relief cause it meant my speakers were working ok

Has this problem just started or have you just bought the car and noticed it ?

Unplug the din connector from the rear of the stacker and spray the pins with contact cleaner, repeat that on the HU end. I had similar problems (rear left and sub cutting out) ended up being dirty RCA plugs on the amp.

yes it is the premium system and affects the left side, and the prob has only just accured, will do what you guys have said and get back to you. cheers guys

Let us know how you go with this one......