Thread: L300 Fuel Pump
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Old 09-26-2015, 03:25 PM   #10
fdryer
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Join Date: Jan 2006
Location: NYC
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2003 L-Series 3.0L Sedan
Default Re: L300 Fuel Pump

It seems like a great buy but are you willing to replace your pump when it fails with this one and be the Beta tester? There are always considerations made when going outside OEM parts; direct replacement or modifications needed the average diyer may not be able to accomplish, actual fuel pressures compared to volume to meet factory specs for L300's, wiring mods, reliability, etc.. Anyone willing to drop a fuel tank and spend a few hours replacing a pump probably isn't interested in a pump without the rest of the pump module assembly. While plastic can become brittle after immersion in fuel all its life, some may find their pump modules falling apart as soon as its handled. Discovering this during pump module removal determines whether or not a quick turnaround restores a car back on the road or waiting for parts not anticipated when a pump module besides the pump breaks down.

As I understand EFI systems in general (correct me if I'm wrong), EFI systems rely on regulated pressures with volume delivery a second factor. Fuel lines are small diameter to allow high pressures with more than sufficient flow volume. I think stock fuel pumps meet or exceed factory specs otherwise there'd be many threads of pump failures. Since these pumps sit in tanks with GM not spending money for access holes in the car structure for pump replacement, I think they balanced this by ensuring pumps last at least thru new car warranty. It appears that the majority of Saturn fuel pumps lasts well beyond car warranty, with many owners never having hints of pump issues. At least until long after many years and well past 100k or 200k miles.

There may be no advantage this pump may have if it has a high flow rate. EFI systems relies on regulated fuel pressures to ensure an exact amount of fuel is injected at precisely the right time. Injection pulses in milliseconds tends to count on high pressures to push out small amounts of fuel from a few hundred injector cycles at idle to several thousand per minute. Since flow volume, in my opinion, takes a second seat to pressures, any changes to pressures has a direct influence on the amount of injected fuel. The O2 sensor providing continuous feedback on combusted gases to the the ecm allows the ecm to continually fine tune air/fuel mixtures to stay within the ideal a/f ratio, 14.7:1. Usually, any slight fuel pressure change outside the regulated range is compensated as the O2 sensor detects it to tell the ecm. The ecm then adjusts on-the-fly until pressures drop enough to cause out of range problems with an error code.
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