Most of the electronics run off of a 5v source. Just cause the alternator is producing 13.5v doesn't mean everything is getting 13.5v. The BCM reduces that voltage and sends it out to the car electronics.

 

I have contemplated switching up the A1000 and walbro for a 340lph but I would have look at how I would go about eliminating the surge tank and 1000 from the lines and whatnot. But I'll leave that for the possible future.

I just want my car to run well right now. I was running ridiculously rich so I wanted to get a new tune to remedy it. I'm not looking to make a crazy amount of power. I just want a decent amount of safe power.

 

If you're running rich you have more than enough fuel being delivered. And rich is safe to an extent. So what is the issue/question?

 

It sounds like he opted to off a twin pump set up in favor of a single Aeromotive pump

 

The question I thought was about the fuel pump. That receives alternator/battery voltage. The ECM triggers a relay - that is the extent of its involvement. The BCM is essentially a compact arrangement of relays and fuses controlled via CAN I/O. I don't think there is any voltage regulation in the BCM.

 

robert k is right on that one, pretty much everything sees 5 volts, one of the various computers in a car will drop the 12v+ down to 5v with a couple exceptions. they just use resistors to do it though

fuel pump and coils however do see 12v+

 

It was running rich even at idle. I was even fouling out plugs. The tune was really out of wack so I didn't drive it. Changed the plugs and brought it to tuner. During the tuning session he said it was running out of fuel up top.

They're looking into it today.

 

They're saying it might be the Walbro because they go bad from time to time. I know this is a possibility but is it likely? I hate throwing money at something just to trouble shoot it.

I myself observed in the past that the FPR gauge would just drop to 0 when you shut the motor off. Perhaps the check valve went bad on it?

 

255's do go bad a lot. They aren't very expensive. Expect to pay around $100 for one, although they do go for less and your shop should be able to get it for you for cheaper than 100$.

I know one of our former members had his car blow because his 255 went bad and he never replaced it after a few years.

I doubt the fpr is the problem, but you could always inspect it to be safe. They are really simple to pull apart.

 

thats normal

 

I thought it's supposed to hold some fuel pressure when you turn off the motor?