troubleshooting???

[jiggyj]

I bought my pro flo about 1 1/2 years ago; it is on a 406 sbc with victor jr heads and a flat tappet cam with about 300 duration and 525 lift. Its installed in a 1984 corvette. I have had some minor problems from day one. The system would start and run fine, but the hand held programmer would constantly restart or freeze, so it makes adjustments very hard to do. I have come to find out the more timing I pull out at idle the less it interferes with the hand held (and my digital dash also has interference in it now as well . I called tech line multiple times and talked to two different gentleman, they both seemed lead me to grounding problems which I replaced all the ground straps and added extra ones. I pulled the motor last winter and freshened it up reinstalled the kit and it’s doing the same thing now. Does anyone have any ideas at all? I have switched the hand held out with my friends and his does the same thing in my car, so it’s not the programmer. I am lost and very burned out on this project, so any other ideas would be great,:confused:
Thanks
Justin Johnson
Justin.johnson77@yahoo.com
Oh by the way some things I have tried consist of changing
The power and ground sources for the system
New cap rotor and accel super coil
Added multiple new ground straps

[S. Armish]

Every once and a while that happens to us here too. The hand held module is very susceptible to interference from the ignition system. As you've already found out, this condition can be difficult to troubleshoot. One thing you can try is using a long serial cable to get the cal module away from the car (just as a temporary test). Get a 10-12 foot extension. Start the car and move the cal module away. Does it still freeze, restart, etc.? If no, then you know the interference is external to the module. If it still hiccups, then you know the interference is being transfered through the cables themselves. Refer to the wiring diagram that came with the system and make sure that any circuit contained in the branch of the harness that connects to the cal mod is physically away from any ignition related circuit. If none of that works, you can send the cal module back to us for inspection.

[jiggyj]

Thanks I will try the long lead and get it away from the car, I tried my friend’s cal module and his works fine in his car, but in mine it still restarts and then eventually freezes, so I don’t believe that is the problem. Can running a super coil cause interference?
Thanks for the fast response, between all of us I bet we can get it figured out :cool:
Justin

[S. Armish]

There are many situations/conditions that can cause ignition interference. Are you running any kind of capacitive discharge ignition...MSD, Crane, Accel, etc.? If you aren't extremely careful with wiring, these are notorious for causing noise problems.

[jiggyj]

I am running a gm distributor w/ the pro flo cross over kit in it with an msd cap and rotor along with a hei supper coil from accel. I tried holding the hand held out the window and away from the car and it did the same thing? I don’t have any noise interference through the radio or any thing like that, just the hand held and my dash flickers and surges. For example I will try to change the tune and in the middle of it the hand held will just restart like I cycled the key, but the motor and ignition does not hesitate or stumble at all. Then last month for the first time it totally lost all of my saved settings so I had to start completely over.
Any other ideas?
Thanks,
Justin Johnson

[jiggyj]

any other ideas???
thanks
justin

[S. Armish]

I tried holding the hand held out the window and away from the car and it did the same thing?

That means the interference is coming through the harness. Make sure the powers and grounds for the Pro Flo harness are isolated from anything tied to the ignition system. One quick thing you can try is to run extensions from the pink/black wire and the ground lug on the Pro Flo harness directly to the battery. This will effectively bypass anything else in the car. If it works fine that way, you can start to narrow it down.

[jiggyj]

The system is grounded to the back of the heads then to the frame from there, then two more ground straps from the engine to the frame.
I unhooked the power wire and put it directly to the battery and it did the same thing. Does it make sense it gets worse the hotter the car is??? Thanks again for the ideas and the help, we will get it fixed eventually, :confused:
Justin johnson

[S. Armish]

The ground lug on the Pro Flo harness is supposed to be bolted to the back of the head normally BUT...I would disconnect it there and run it direct to the battery along with the power lead (pink/blk). You may have to make an extension to do this.

[jiggyj]

thanks, i will give this a try tonight and we will go from there.

[five five]

I had the same problem. My hand held module constantly froze and was extremely unreliable.

Food for thought:

Later, and all at once, I switched to an Optima Red Top, mounted it to the rear (an El Camino), rebuilt the entire primary battery cabling using high quality multi-strand cable, installed an MSD Digital 6, HPC II coil, and Accell 10.8mm race wires, used major size ground straps directly to the frame and body, and used soldered connections everywhere. I also replaced the HEI cap-coil entire distributor with a Mallory ball-bearing Hall Effect distributor.

The computer is mounted in the interior where the passenger side floor vent used to be, just on the other side of an .050" piece of aluminum from the MSD box and coil, the aluminum filling the void in the firewall where the heater and fan assemblies formerly resided. There is no other shielding.

Since then I have never had any issues with the module. Works every time, never resets or fails like it did every 5 minutes before.

What I think is the solution in my case:

I believe that the battery and cabling with the major effort at grounding is what really fixed the module's problem. The 10.8mm shielded spark plug cables may have helped once the MSD and coil were installed, but no way to tell.
BTW, the shielding works so well that my inductive timing light will not pick up a signal. I have to replace #1 wire with an 8.8mm wire to time the engine.

One thing that really helps is to always remember that Benjamin Franklin got it wrong....
... electricity flows from (-) to (+), not the way we were taught to think.... those negative grounds are actually the source of electron flow... they are critically important.

The MSD is in close proximity to the main batt cable penetrating the firewall aluminum, the main EFI harness also penetrating the firewall in that locality, along with the EFI ignition amplifier also in that location. Although there ends up being quite a lot of wire runs in the area, by keeping the different harnesses at least a few inches from each other, there have been no EMI or RFI problems.
http://i20.photobucket.com/albums/b203/aero80/digi6install.jpg
Eric

[jiggyj]

Well back again, I have remounted all of my grounds and I still can’t find my problem. Is there anyway the actual computer is bad???

[jiggyj]

Well any other ideas????
Also I converted my distributor over with the parts supplied in the kit and I now want to run a small cap or a distributor that is setup for this kit. Which one will work?

[shaun callaway]

Well any other ideas????
Also I converted my distributor over with the parts supplied in the kit and I now want to run a small cap or a distributor that is setup for this kit. Which one will work?


You can use a Mallory small cap part number 6148201 ( http://store.summitracing.com/partdetail.asp?autofilter=1&part=MAA%2D6148201&N=700+115&autoview=sku ) and a MSD baster coil part number 8202 ( http://store.summitracing.com/partdetail.asp?autofilter=1&part=MSD%2D8202&N=700+115&autoview=sku )

[jiggyj]

I put the new distributor in the car; it fixed the feedback to my dash, but the hand held controller still re-sets constantly. Do you have any other ideas?