[73LeMans]

I have no way to condense what I'm asking....it s a problem I'm well aware of. Apologies up front. I'm working on it.

Posting this in the Street section because I feel its something geared more to making a "race" car street friendly than something one might see on non street driven car. I might post this in the Electrical section too.

Anyone running Aeromotive's Fuel Pump Speed Controller (P/N 16306)? I've got one on my Stealth A1000 pump and its driving me nuts. Here's whats happening -

The intent of this piece is to keep fuel pump RPM commensurate with engine RPM until a user defined RPM is set, whereas the pump then goes into Full mode pushing 100% of the fuel. Whats happening at idle (1000 rpm) is the controller is seeing random false spikes in RPM telling the pump to go to Full mode for a flash, then not, then Full mode, then not, then Full etc, at a rate of about 20x a min. I've even confirmed the voltage spikes at the pump with a meter. To protect the system, the controller senses the fault and initially was shutting off the pump.

On the recommendations of Aeromotive, I've gotten to the point where the pump no longer shuts off. That's good - but the problem is I'm still seeing the Full light flash intermittently as I'm idling the car. Perhaps 10x/min.

I've read all of the Aeromotive Tech Bulletins. I've even spoken to Brett in Tech Support and he seems to be stumped as to whats happening. (and is a tad slow in responding) The consensus is electromagnetic interference is the cause. I'm not convinced.

I used braided metal sheathing over the tach signal wire from the MSD to the FPSC. Just in case, I also ran a brand new wire here because the old one had a butt connector in it. This wire is completely isolated from others and is run outside of the glove box (MSD is there) to the controller for testing. The full light still flashes erratically, which means I still have a dirty signal on this input wire to the controller.

Here is what I also observed. As mentioned, idle in the car is about 1000rpm. If I lower it, it cleans up the signal and the Full light flashes less, it at all. If I stab the throttle, consistently what happens is the full light then starts blinking erratically. Not consistent with rpm, but consistent with the tip in of the throttle. Each time I tip in, the Full light will start blinking erratically. Could the MSD be causing this? Seems like it. It an older 6AL box...23 years running.

If so, and even though the Aeromotive Bulletins say that an EMI filter is only needed on the wire from the controller to the tachometer, does anyone see a problem with building the same EMI filter on the MSD input wire into the controller? The resistors and capacitors come tomorrow, so wanted to see if anyone though this was a bad idea before I went ahead and just did it.