Flow issues in 09 Mazdaspeed 3

09MS3DISI · #1 06-05-2016, 04:01 AM

Recently installed an unopened still in box and wrapping, used HFS-3 system in my MS3. The original purchase receipt was still in the box as well. Installed the system and wired according to the car specific diagram on here, triple checking the ECU wiring. Turn the system on and purged it, everything looked fine. Went for a drive and as soon as I hit the factory IDC threshold (~42%) the system started flowing, but didn't stop once throttle was lifted. Turned the system off, and back on, meth still spraying even though IDC is like 5%, car bogs and AFR goes super rich via Cobb Accessport V3 monitoring. Turned the system off. I periodically turn it on and 95% of the time it will indicate flow and AFR indicated spray (rich) even while on 5-10% IDC. The other 5% of the time it doesn't just start spraying, but will once Threshold is met and won't stop. I thought maybe it's picking up false signal on the IDC sense/user cable so I added extra heat shrink and electrical around the connectors to try and better shield them, but no change. Any ideas?

09MS3DISI · #2 06-05-2016, 04:25 AM

If it helps any

Richard L · #3 06-05-2016, 07:15 AM

Can you re-post the pics. Need to see the top and bottom side of the circuit board. Hi-res pictures if possible.

09MS3DISI · #4 06-05-2016, 02:58 PM

I was told by the original purchaser that it was factory configured for the MS3.

Richard L · #5 06-05-2016, 05:17 PM

Thanks for the pics.
I have spotted a possible cause for the weird behaviour...

Can you de-solder or know someone who can?

Richard L · #6 06-05-2016, 05:29 PM

This modification was not done at the factory but in the US. It was imported to the US in April 2015.

09MS3DISI · #7 06-05-2016, 05:46 PM

I'm a micro miniature circuit card repair tech, I think I can handle that lol. Don't know how I didn't spot it. Thanks Richard I'll get the solder bridge removed and let you know the results.

Richard L · #8 06-05-2016, 09:04 PM

Your skill is very handy for this. Hope this will cure the problem. It is very rare.

09MS3DISI · #9 07-05-2016, 05:24 AM

So I got the solder bridge taken care of, and then I noticed this. It's on the plug for the user cable and there's actually a wire connecting the two leads under the solder. Should this be there?

09MS3DISI · #10 07-05-2016, 05:34 AM

Correction. It's a resistor soldered between the two leads. Same question though, is it supposed to be there?