Fuel pressure question
05-04-2009, 08:47 PM
#1
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Fuel pressure question Ok, in theory bumping up fuel pressure would make the car run slightly richer across the board, including wot correct?
I did this trying to fix a lean issue in the upper rpms with no effect on the afr whatsoever. Any opinions?
I did this trying to fix a lean issue in the upper rpms with no effect on the afr whatsoever. Any opinions?
05-05-2009, 08:12 AM
#2
1.Pump was already max'd out @ the original psi.
2.If the engine is still running in closed loop, the added fuel could be removed by the PCM correcting to a commanded afr.
3. Increasing psi does not necessarily increase volume. Actually, as FP is raised, volume goes down.
Is the fpr boost referenced?
Have you datalogged the system., including FP???
2.If the engine is still running in closed loop, the added fuel could be removed by the PCM correcting to a commanded afr.
3. Increasing psi does not necessarily increase volume. Actually, as FP is raised, volume goes down.
Is the fpr boost referenced?
Have you datalogged the system., including FP???
05-05-2009, 09:55 AM
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I'm running dual 340s -8 feed -6 return fuelab boost referenced regulator and 60's. Fuel pressure does rise with boost and holds steady, doesnt fall off. I'm wondering if maybe my injectors are maxxed? My PE tables are maxed out from 4k up and it creeps up to about 12.4 afr by 6100 rpm.
05-05-2009, 08:42 PM
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Look at the injector duty cycle in the data logging as to whether its staying, lowering, or rising. Even though, if the injectors were at static flow, with fuel pressure increase it will raise the flow rate regardless. Do you have any other tables conflicting the the fuel pressure change? Also is the pulsewidth lowering now for any reason?
Last edited by avb0119; 05-05-2009 at 11:17 PM.
