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Have you tried cleaning the maf?

As a side note, the only way Ive been able to find vacuum leaks is with brake cleaner (in small quantities) and watch the fuel trims. On efi cars when you perform a test like this the ecu will actually pull fuel and the rpms will stay the same or fall depending on how much you use.


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Discussion Starter #5
I tried propane test and could not find a lea around intake area. The LTFT also does not change with increased RPM. I guess its worth a shot though since it is not a very expensive, nor difficult job.
 

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Discussion Starter #6
Cleaned the MAF and also replaced it with one from my fusion which was the same part #. No change.
 

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Check for inlet manifold leaks and other small vacuum leaks using a meter/yard or so of windscreen washer sized tubing; one end just near your ear canal while listening for the sucking sound of a leak while moving it around the manifold near where it meets the head (especially the underside of the manifold and at each end where the bolts tend to loosen burning out a small pieces of the head gasket) with the engine idling. Do this with engine cold and then engine at normal operating temperature as the small gap between the head and the manifold gap can open and close as the head and manifold expand and contract with heating and cooling. Or use one of the mechanics stethoscopes that allow you to use the tubing part only by removing the metal end used to listen for mechanical noises. Note the old system of checking for vacuum leaks with sprays and fluid are fine for carburettor based engines but I have found they often won't work well on computer controlled car as they will adjust the mixture too quickly to notice any change in revs. You will also often be fighting gravity if the leaks are on the lower side of the manifold and oil, butane etc sprayed may just fall towards the ground rather than being sucked into the gap between the manifold and the head.
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Discussion Starter #8
I checked fuel pressure last night and its between 25-30 psi. Seems kind of low. Weak fuel pump? Is there a pressure regulator on these?

I think I'm going to just go ahead and replace intake since it's a pretty easy job.
 
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