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beepbeep beepbeep is offline
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Join Date: Jun 2001
Location: Sweden
Posts: 5,565
Stock CIS pumps are tailored for CIS: 7 bar system pressure. While two 930 CIS pumps will probably work fine on EFI car, I suggest using ordinary EFI pump of suitable size.

FPR works by attaining constant pressure across injector. So it will lower the fuel pressure is there is vacuum in plenum and raise it if there is a boost pressure on the other side.

First of all, make sure fuel lines aren't gummed up with deposits. Then change fuel filter and check fuel pressure again. If it still cannot hold pressure on throttle, change pump. Bosch 040 pumps are good and reliable.

Check pressure with new pump. Is still not OK, change FPR. Use ordinary 1:1 FPR. Raising rate FPR are only band-aid.

Once your fuel pressure is OK, do AFR run again. If everything is OK then you are square. If not, you might need TEC software and check duty ratio on injectors.

But I'm pretty sure filter or pump is main issue here.
Thank you for your time,
Old 05-21-2008, 02:22 PM
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