RFI Help... Snoman

[ConceptKid]

I had the plug wires replaced in my 3500 van. I just recently started having this problem though. On any weak radio stations or on my nextel phone, as soon as I crank the engine, my signal dies. The nextel is simply a cellular phone, and it is in no way connected to the truck. any suggestions would be appreciated. The dealer suggested unplugging the alternator and trying that, but that did not seem to help.

I am sure it is something going bad, But where to start? Thanks again

[GMCTech]

Replace your cap and rotor.

 

Hope this helps.

[snoman]

Did the problem get worse after you replaced plug wires? Some brands of wire have a lower resitance per foot that others and you want the highest possible resitance per foot (10 to 20,000 ohms per foot minimum is desirable) Also have you install resistor plugs yet even if they are not called for as they can help alot too. I sounds like you are getting RFI generated by ignition wiring as some cars for some reason are bad about this. By adding higher resistance to circuit and to the plugs you "soften" the arc spike and greatly reduce RFI from it. Altenator noise as a rule will only come through the power leg but you say that you are not plugged into car for power so we will rule that one out as a cause. Try this and get back with me and PM me if you like too.

[8100HD]

Looks like the wires that were just replaced are some cheapies....go out or take the van back and request a good quality shielded wire set.

[snoman]

Looks like the wires that were just replaced are some cheapies....go out or take the van back and request a good quality shielded wire set.

They need to be resitive wires as some cheap one are not really this type. Hi Preformace wiring (wiring marketed as such) is rarely resitive and should be avoid. Sometimes you will see it listed a "Supressor Cables" if so, get them.