I think I have a fuel pump problem. Need expert advice

[ez112]

So my many bolt on Lightning runs rich. REALLY rich. I have a wideband and it says its in the 9's and you can smell it nicely under WOT. I never figured this many mods and I have a running rich problem.:shrug:

I did a datalog and noticed my FPDC is at 1.00. It's ALWAYS at 1.00 and never moves. This isn't normal is it?

I was reading a little about some resistor or what not, so could that be it?

I was beginning to think I had MAF problems at first but I figured I'd take a look at this first. Any help would be awesome.

Thanks!

 

[SID297]

The maf can cause that for sure. I'm not sure about the FPDC though.

 

[lkatya]

Could be lots of things but you can take the resistor off your suspect list

When the resistor starts failing you'll see lean conditions.

 

[ez112]

It does seem to be a MAF issue. I returned the canned tuned PCM back to stock and now my LTFT's are 1 at WOT when before they were well under that.

Let's see if a real tune helps me out...

 

[SID297]

Def get a custom tune. Canned tunes can be hit or miss.

 

[ez112]

Well I was gonna wait til my tuner came back to me with some information, but he never did. Pay extra to get the tune, but the review/adjustment is gonna take all week with no responce...

Anyways, I don't know what more the tuner did but take out a bunch of timing. He adjusted for my new BA2600 MAF, and there is a NOTICEABLE change and it's a dog now. A/F is even LESS than before. A/F in the 8's according to the log.

What else can I look at to see whats screwing me up?

 

[SID297]

An A/F in the 8's can be indicative of a problem that is causing the truck to go into limp mode.

 

[ez112]

Whats limp mode?

I mean the truck behaves perfectly fine is the thing. Runs drives fine. WOT, it's still fast and doesn't hesitate or ANYTHING!

I just changed plugs about 3000 miles ago? Fuel filter last year.

I maintain it pretty well so I thought?