Interesting Info For EFI Guys Experiencing EMI/RFI Issues

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GMachineDartGT

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Like many on the board, I am using a FiTech efi retrofit. I was an early adapter and dealt with improperly packaged fuses, burnt deutch connector and failed tach driver, on 2 systems, my own and a customer. Once ironed out, the system runs well but recently has had emi/rfi issues. Since I am lucky enough to have a career electrical engineer and car guy in the family, we went through the usual band aids. RF sleeving and grounds on the signal wire, re routing wires, etc. Bottom line is nothing seems to be working. My small block stroker is stock appearing with correct 340 valve covers and OE seperators. I use an MSD E curve distributor and a tube coil (USA Made) in the factory bracket on an air gap intake.
After swapping out the coil, rechecking soldered connections, ground potentials, I came across an interesting read - Magnecor Race Wires
After discussing the issues with an electrical engineer and an RF specialist, it seems that spark plug wires could be the culprit. I am going to try a set and report back. While I have read tons about people with this type of issue, I haven't read where anybody had a real solution to repairing the source of the issue. I have a feeling the big name plug wire companies haven't really addressed this issue.
I welcome all thoughts and experiences.
 
Do you have a plug in cigar lighter USB charger? Those things use a switching regulator and the cheap ones emit all kinds of radiation. Some modern cars have had problems with them affecting the tire pressure monitor and other systems. A friend of mine who troubleshoots electrical problems for a dealer says the first thing he does is unplug them and it has fixed the problem.
 
I have read some of the same issues and different causes from wire routing, to the things that you have already addressed. The one thing that Holley did was to build their Sniper EFI distributor with a Hall effect signal to eliminate any noise to the ECU unit. It seems like there have been a few mentions of different distributors being the cause of problems.
 
Have had good results with the msd wires 8.5 with the sniper . What I have installed are the noise suppresses I’m not sure of the correct name for them , we use them for RF noises on fax machines lines and they are installed on some high voltage lines in the back of the machines and I’ve installed them on the distributor wires from the msd 6L box and the msd coil +- wires. On the Holley forum on face book there was a post where a guy was running his I phone around the engine bay and his phone was acting erratically due to RF issues. Alternators have caused RF issues aswell as thermo fans have caused their fare share of headaches as well.
 
Do you have a plug in cigar lighter USB charger? Those things use a switching regulator and the cheap ones emit all kinds of radiation. Some modern cars have had problems with them affecting the tire pressure monitor and other systems. A friend of mine who troubleshoots electrical problems for a dealer says the first thing he does is unplug them and it has fixed the problem.
Jut listen to an AM radio station when you plug one of those USB chargers in, sounds like a police siren through the radio!
 
Pishta you can do that with a small radio on a am station hovering over the engine bay if you don’t have a working radio in the car .
 
I'm running old(er) Mopar solid core (steel stranded wires) sparkplug cables with my MegaSquirt 3X.
Leanburn distributor, 7-pin HEI and MSD Blaster SS e-core coil.
Turn on the AM-radio in my '73 Dart and you'll think it's a Geigercounter.

Noise filtering is 'on' to filter out any possible trigger signals that shouldn't happen but the engine revs to 4750 easily without missing a beat.

Not quite sure anymore but I do recall to have suspression sparkplugs.
The Iridium type.
 
I'm running old(er) Mopar solid core (steel stranded wires) sparkplug cables with my MegaSquirt 3X.
Leanburn distributor, 7-pin HEI and MSD Blaster SS e-core coil.
Turn on the AM-radio in my '73 Dart and you'll think it's a Geigercounter.

Noise filtering is 'on' to filter out any possible trigger signals that shouldn't happen but the engine revs to 4750 easily without missing a beat.

Not quite sure anymore but I do recall to have suspression sparkplugs.
The Iridium type.

You`re not suppsed to run solid wires with efi --------
 
The problem with the FITECH SNIPER is the ecu is built in the throttle body and is more sensitive to rfi issues but if you run your cabling correctly and keeping certain wires away from others take some precautions usually everything pans out well.
 
You`re not suppsed to run solid wires with efi --------

I know, but my MegaSquirt-install doesn't seem to care.
The cables are prob. be due for replacement fairly soon I would guess. They should be well over 10 years old by now.
Still want to do a dark waterspray test to see if they are leaking sparkies, but the way the engine run it doesn't seem likely.
 
The problem with the FITECH SNIPER is the ecu is built in the throttle body and is more sensitive to rfi issues but if you run your cabling correctly and keeping certain wires away from others take some precautions usually everything pans out well.

Not all the time. I’ve done a dozen of these without problems. However, mine was ok when I put the wires I have on, but without changing anything, I’ve begun to have issues. The Magnecore tech info suggests some wires have a carbon coating that can burn off. I’m thinking this is a possibility.
 
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