[DeTomaso] final verdict on EFI

[Doug Braun]

Justin,

I feel your pain.

I'm still in the throes of fine tuning my Powerjection 3 system and
encountered two separate hardware failures that both resulted in having to
return the system to Professional Products for repair-replacement.  The
first time, the wideband input circuit was faulty which I troubleshot by
connecting another wideband sensor with no change in readings.  The symptoms
were" the A/F ratio read 18:1 at idle with momentary spikes down to 12:1 but
the exhaust smelled richer to me and the unit would not go closed loop.

After I got the fixed unit back, it worked great until I realized that the
replacement unit was failing to save the learned parameters at turn-off, but
only when the unit was hot.  I discovered this problem by taking screen
shots of the tune parameters and comparing the ECU's contents to the screen
shots at the next turn-on.  The symptoms were: whenever I shut the unit
down, while hot, and then tried to restart, it would be at 11:1 fuel ratio,
stinking like mad, until the ECU learning process had time to correct it
again.  Cold restarts were fine.  I don't know if your Powerjection 1 saves
it's learned parameters at every turn-off like the Powerjection 3, but every
time I shut it down with the PC connected, I can see the message, "Saving
ECU parameters" which transfers the ECU's learned RAM contents to the Flash
memory.  In my case, a bad timing capacitor in an RC shut-down timing
circuit was causing the ECU to shut off right in the middle of the RAM to
Flash transfer so the next time it started it would run badly unless I went
back the to basic tune.

At this point I'm waiting for the unit to return - they replaced the bad
capacitor and FedEx is returning the unit as we speak.  I'll let you know
how well it runs (or doesn't) after I get it back.  At this point, I would
recommend people stay away from this brand until I use it longer and find it
to be reliable and work well.

Doug  Braun
blue 73L #5505

On Tue, Oct 4, 2011 at 5:43 PM, Justin Greisberg <
justingreisberg at hotmail.com> wrote:

>
> i appeciate that it all should be logical and fixable, but the problem I am
> having is resistant to change.  Under part throttle acceleration, the AF
> ratio goes way lean and the car bogs.  bogs horribly and almost stalls.
>  cant drive in traffic.   I tried adding more fuel.  No change. I tried
> adding less fuel.  No change.  I changed the RPM MAP boundaries (whatever
> that means) to higher numbers for more resolution because I have a lower
> vacuum cam at idle, and that helped a little, but dont know where to go.  no
> one at the company can offer any more advice.  maybe something wrong in the
> system.  maybe something wrong in the software.  maybe something wrong with
> me.
> P.S.  I love the comment that "100% working fuel injection means works as
> well as a carb."  It is ironic that I started this project because my carb
> cars are hard to start after sitting for a while.  now I wish that was the
> only problem...
> justin
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