Could low voltage influence the fuel system?

[adv4nced53]

I have a walbro 255, 680s, etc...and I have a very high idle + the injectors are maxing out at 17psi which is unheard of. The volts sit around 12 and when the reading was at 14, i didnt notice any problems. Could the electrical be causing this?

 

[DGajre777]

Yes, voltage plays a huge role in flow of a fuel pump. This is the reason why you see people re-wiring their pumps so the pump gets 14volts instead of 12.

Are you seeing 12volts with your engine on? If you are, it is time for an alternator.

 

[adv4nced53]

Yes I am but not all the time. I was just messin around outside before I took out the alternator, the car was at 14V and was running good. All of a sudden the idle went up and when I looked the reading was 12V. I've changes 2 alternators this year but whatever autozone lifetime guarantee

 

[turboAWDfanatic]

Alternators have been an issue for a lot of DSM'ers. Heck, go look through the archives of the clubDSM website. People have gone through multiple alternators back-to-back, and there was many theories as to why. Despite the theories and rumors, there are 2 MAJOR contributors to bad alternators. Fluids leaking on them (oil or power steering), and REMOVAL OF HEAT SHIELDS. I went through 2 in one month though with heat shields in place and no leaks.

My advice is to pony up for a good NEW OEM alternator rather than refurbished. They will be warrantied and will definitely last longer than Autozone or Kragen.

 

[DGajre777]

Mitsubishi no longer makes NEW OEM alternators. Even the NEW OEM alternator you get from a dealership is rebuilt. The only company that sells 100% parts NEW alternator is BOSCH and they are in the range of $400+.

 

[adv4nced53]

Well I just replaced this one, tested the battery, and changed one of the terminals. Started up at 14V but at some points it dipped down around 13V and stayed there for a bit. Idle is fine now but the AFR at idle was 18:1, which seems high. I don't know if that is normal because I'm comparing to the 13:1 idle that I had before I put in the cams. Kinda doubt it is though...

More work tomorrow!!!!

 

[Indylx]

i had an alternator issue too....i bought one from advance and was good until i sold it

 

[adv4nced53]

idk im not even sure if in my case it was the alternator because my voltage is still fluctuating...ground wires?

 

[spyderturbo007]

Well I just replaced this one, tested the battery, and changed one of the terminals. Started up at 14V but at some points it dipped down around 13V and stayed there for a bit. Idle is fine now but the AFR at idle was 18:1, which seems high. I don't know if that is normal because I'm comparing to the 13:1 idle that I had before I put in the cams. Kinda doubt it is though...

More work tomorrow!!!!

Have you checked for exhaust leaks? Mine is leaking at the flex section, again, and at idle the AFR drops to the 17:1 range. At cruise it's pretty much right on, but seems to fluctuate a little more than it did before the leak. I can't see any way that a 1v drop on a 255lph FP is going to cause you to run lean. Maybe at 25psi of boost, but not at idle.

I'm going to move the damn sensor in front of the flex section, I don't care if I kill it quicker or not. I'm tired of this crap.

 

[99gseclipsenism]

So does anybody have the rewiring instructions for the fuel pmump? Lol

 

[crimsondragon]

Seriously? You brought up a dead thread to ask for instructions on how to rewire the fuel pump which has been covered many times? I'll provide the link to where you can find it. Use your hand to use that mouse to find it instead of using it to masturbate.
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