Fuel pump?

[89VERT]

MM will pull strong to around 4000 rpms under WOT and then won't rev higher . Started this tonight . Had a very similar experience when the MM was new and it was the fuel pump . Any other ideas ? If I remember correctly the fuel pressure in the rails should be around 40 psi?

[justbob]

Yes, that is the symptoms of a bad pump. But I would datalog FPDC just to verify.

This was posted live, in real time.

[fastblackmerc]

Bad fuel filter?

[Taemian]

I have a fuel pressure gauge if you want to borrow it. Give me a call if you'd like.

In other news, my Marauder came back from the install shop and the new engine is being dyno'd at BrownBrosFord tomorrow! We gotta all get together for a cruise sometime soon.

[89VERT]

Thanks for the offer of the gauge Ian , I changed the fuel filter and filled the tank with Chevron 94 and the problem seemed to go away . But not for long . I had a buddy hook up an OBD scanner on the car , but of course it would not do it then . All the readings were great . Fuel pressure was at 39-41 psi under WOT ,but would drop to about 25 for an instant when I lifted my foot of the accelerator at WOT..Any other ideas anyone ?

[Taemian]

Did you solve this?

[89VERT]

Thanks Ian for the follow up . I changed the fuel filter and ran a couple of containers of fuel injector cleaner through . Seemed to fix it .

[Taemian]

Must be nice. I just got a $3K bill at BrownBros for my car. Up to about 10K for the entire rebuild now, still not done.

[89VERT]

Ouch ...that's got to hurt , but hopefully will be worth it when you're putting some serious power to the ground . Keep me posted on your progress .