So - my tuner is struggling with my car, and this is what he's finding (bearing in mind he's never seen a Cobra Mustang - 2.3L Whipple, 60lb injectors etc - never tuned one before - because this is Australia and the Terminator was never released here) - but he's an experienced tuner.
When the car goes off idle the mixture goes really lean. The harder into it, the leaner it gets and the more worried he becomes. The ECU reports back via the SCT logging that the fuel pressure is dropping and so it is increasing the voltage to the pumps, but they're not increasing pressure to the fuel rail. This is either because they're NOT getting the extra voltage, or they're driving so hard they're cavitating (I don't believe this is the case). Bearing in mind there is now a 40a BAP fitted (it was used when I bought it), therefore it may be faulty OR it may be wired incorrectly. It is wired with the FPDM between it and the pumps. Adjusting the tune appears to have no affect on the fuel pressure or the mixture.
So, as the next step - I've asked him to measure the voltage at the pumps to see how it responds to the ECU. What voltage typically should he see at the pumps at idle, just off idle, mid throttle etc? 6v, 10v, 14v, 16v etc?
Finally, do BOTH pumps run off the FPDM or is one pump wired with 12v all the time and the FPDM spools the other up and down, or do both run off the FPDM?
Thanks in advance guys - Jeff
When the car goes off idle the mixture goes really lean. The harder into it, the leaner it gets and the more worried he becomes. The ECU reports back via the SCT logging that the fuel pressure is dropping and so it is increasing the voltage to the pumps, but they're not increasing pressure to the fuel rail. This is either because they're NOT getting the extra voltage, or they're driving so hard they're cavitating (I don't believe this is the case). Bearing in mind there is now a 40a BAP fitted (it was used when I bought it), therefore it may be faulty OR it may be wired incorrectly. It is wired with the FPDM between it and the pumps. Adjusting the tune appears to have no affect on the fuel pressure or the mixture.
So, as the next step - I've asked him to measure the voltage at the pumps to see how it responds to the ECU. What voltage typically should he see at the pumps at idle, just off idle, mid throttle etc? 6v, 10v, 14v, 16v etc?
Finally, do BOTH pumps run off the FPDM or is one pump wired with 12v all the time and the FPDM spools the other up and down, or do both run off the FPDM?
Thanks in advance guys - Jeff