Ignition interference 93 Blazer

abbylind · Post by **abbylind** » Sun Dec 04, 2005 11:14 am

Hi all
Ive got a 93 full size Blazer with the 5.7 engine. Im getting ignition noise now through my scanner and two way radios (both mobile and portables) Replaced the distributor cap, rotor, spark plugs and wires (suppression wires from autozone), still no joy. I used antiseize compound on the plugs when I installed them. I also tied a grounding strap from the hood to the body. Ran a probe from a portable scanner to the engine and found its definately coming fron the ignition system

Anyone know of a good solution? Maybe a good source of suppression wires?

Thanks in advance
Fowler

firegood · Post by **firegood** » Sun Dec 04, 2005 11:56 am

where are the power wires going to power the equipment? where are the antennas mounted.

thebigphish · Post by **thebigphish** » Sun Dec 04, 2005 5:03 pm

are you sure it's IGN noise? I'm a big fan of putting a cap across the fuel pump terminals....it's helped me.

abbylind · Post by **abbylind** » Sun Dec 04, 2005 6:29 pm

The wiring goes to the assy panel on the fusebox. The antenna for the scanner is on a splitter with the AM FM radio. Ive had it hooked up this way for a while with no problems until recently. Its definately ignition noise that changes with the RPM of the engine. If I bring my XTS portable or a handheld scanner in the vehicle i get the same results.
I can also hear ignition noise on my 800Mhz Orion. Its antenna is mounted on a Larsen bracket on the left fender. Power comes from the assy panel on the firewall

Fowler

Mikey · Post by **Mikey** » Sun Dec 04, 2005 6:58 pm

I had the same problem with my 97 Chev. Blazer and it turned out to be the Diode in the Ac Delco Alternator. Took it to an alternator shop and they replaced the diode and Voolaaa no more alternator Wine. Just a thought you might want to try. The Alternator will still charge and check out fine, but if the Diode is out, it will give you a Wine that increases with engine RPM.

Mikey

gws · Post by **gws** » Mon Dec 05, 2005 6:03 am

The fuel pump on the full size chey's are often a good source of "ignition" noise. A pain to correct but usually the problem.

abbylind · Post by **abbylind** » Mon Dec 05, 2005 12:19 pm

Its not an alternator whine (Ive repleaced the alternator too) its a cracking popping sound which changes with the RPM of the engine. Does the fuel pump vary with engine RPM?

Thanks
Fowler