Fuel Pressure Control.

[DaveEFI]

Surely the best is to fix the fault on the board?

James

I've repaired quite a few boards with faulty pump drivers. Not quite sure why - but I've a feeling the ZTX 450 may not be the best transistor ever, despite its high current rating. I tend to fit the good 'ol 2N2222 which is more than adequate for a single auto relay.

[nathaninwa]

Ah yes. I see where you are coming from but if the MS fuel pump control has failed what turns the pump on?

If my interpretation is correct, the pump turns on when the TPS is greater than 15% and in less than 2 seconds??

As I said in an earlier post. That's my secondary pump for my staged injection. My primary side works as normal. I'm just showing you the way to program the output using the "and/or" setups

With it like that, my pump cycles for 2 seconds with a key on condition, then runs whenever the tps is above 15%. If you change my tps setting to rpm and greater than 10, it will prime, then run like you want it to

[Trump]

OK.

Think I have it. One of my problems was that I assumed that the prime pulse was controlled by the fuel pump circuit. I now know it is not.
Now I have my fuel pump control (Inj G) set to RPM > 10 or TPS> 10. For the first start of the day or in cold weather I apply some TPS when I turn the key on. This will give fuel pump while throttle is applied and a priming pulse.
If I have to pull the ECU again I will have another go at the fuel pump circuit.

Thanks for your help.