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My truck is sick

F

FlaBouy

Full Member
Joined
Feb 4, 2005
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Well, I knew it was only a matter of time... Surprised it took 18 months..... :D

My truck is sick..... I think it caught that bad strain of TB that was going around.........

Any guesses?



 

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Dune said:
Its got something to do with the air/fuel ratio :p
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Other than the label on the pic, how do you figure? and what's the issue...... :D
 
Your blower is sucking...turn it over.  :laugh:


:kidding: Hope you get it figured out...

 
TheBeast said:
Your blower is sucking...turn it over.? :laugh:


:kidding: Hope you get it figured out...
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There may be some truth in that...my issue is from about 4000 rpm on out at 3/4 throttle..........

It would seem halfway through the pull AFR starts climbing quickly.... bad news under boost..... Me thinks I have a partially clogged filter or the Walbro 255 is starting to give up the ghost.....
 

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Logged the truck on the way to work staying out of boost.... AFR's were dead nuts perfect.... Hmmmmm, my plan is to take the stock intank cannister I have in the attic and rebuild a new drop in assembly. Then do a swap. I will document the Walbro install for those that have not seen the in tank unit.

I also plan on running some voltage test on the fuel pump circuit. The aftercooler instructions wanted the aftercooler pump tagged onto the fuel pump circuit. The fuel pump circuit is a 25A, so it should have been OK to do this.... but if for any reason the aftercooler pump is pulling down the voltage to the fuel pump, it would act in reverse of an aftermarket Boost-a-pump unit that increases voltage to the fuel pump to increase it's output. It may very well be that the Vortech pump is pulling the voltage down, causing the pump to decrease it's output.

Dunno..... truck drives fine while in vacuum...... ???
 
EricB said:
I think the problem is in the Flux capacitor.? Just a thought.
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Nope it checked out fine.....  both of them..... :cool:

 

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Looks like you backed off quickly which is good. Were you looking at fuel pressure when this happened? Far be it for me to tell you how to check something electrical :p.......lol. But, an easy way to check it is to pull the fuse, put a fused jumper wire in its place and use low amps probe and see what its doing when your A/F changes.

Good luck
 
trannyman said:
Looks like you backed off quickly which is good. Were you looking at fuel pressure when this happened? Far be it for me to tell you how to check something electrical :p.......lol. But, an easy way to check it is to pull the fuse, put a fused jumper wire in its place and use low amps probe and see what its doing when your A/F changes.

Good luck
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I was not looking at pressure.... I felt it..... the truck nosed over when I am usually sitting vertically looking at the sky..... :D I logged the next pull (part throttle) to see what was going on....

and thanks for the advice, but I have a Fluke logging RMS meter that I can actually put in line with the pump and log voltage to the pump while I am driving around under full load. Then, it is a only a simple matter of hooking my Fluke up to my laptop and replay the log.... I will see any drop in voltage easily enough... We are not looking for amperage... we are looking for voltage....

 
FlaBouy said:
but I have a Fluke logging RMS meter that I can actually put in line with the pump and log voltage to the pump while I am driving around under full load.
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I figured you would........given your background :p. I test them the other way so I don't have to go under every vehicle. I am surprised though that they want you to use the fuel pump ciruit for the aftercooler pump. Running 2 pumps on such a critical circuit seems odd.
 
trannyman said:
I figured you would........given your background :p. I test them the other way so I don't have to go under every vehicle. I am surprised though that they want you to use the fuel pump ciruit for the aftercooler pump. Running 2 pumps on such a critical circuit seems odd.
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The aftercooler pump is small.... I will probably put a shunt between both pumps to see what kinda amperage they draw, but I am sure the amperage is fine since the fuse is holding... Voltage is a different animal though since additive load may impact the voltage drop of the wiring itself... voltage drop is inversely proportional to amperage increase according to Mr. OHM..... :D

If voltage is dropping then the pump output will go down... I suspect that if it were due to the aftercooler pump, then the pump output drop would be across the board, not just at higher RPMs.... kinda hard to tell because the fuel trims will take up the slack of fueling at lower rpms and you could probably never notice....

Anywho, I will go Sherlock Holmes on it's a$$.... Need to get this resolved before the withdrawals get too intense.... :D
 
Motion427 said:
You might have sucked a CAT !!!!!
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Just help him fix it and leave his private life out of it :p :laugh:

Why are you still here Rick.......go fix it will ya >:D
 
trannyman said:
Just help him fix it and leave his private life out of it :p :laugh:

Why are you still here Rick.......go fix it will ya >:D
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Why it drives fine under 84 mph..... :cool:
 
Yeah,could be a voltage drop at the pump with the add ons ,or pump is going south.or maybe the knock sensor is starting to do crazy stuff.Seen a bad knock sensor before that actually shut off the truck while driving.
I was just joking about the cat. :laugh:
 
Motion427 said:
I was just joking about the cat. :laugh:
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You reckon?........ :laugh:

and btw... you do realize I am logging knock sensors all the time, and actually see their input on the log. I would think that would be a bit of a stretch..... but thanks for the effort... :cheers:
 
sssMOkinAV said:
hmmmm, loose nut behind the wheel? ...
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nope....obviously a bad muffler bearing....that could be bad for your tweeters.  Start by disengaging the the king stud on the passenger side and work your way back :p
 
BigBlackAv said:
nope....obviously a bad muffler bearing....that could be bad for your tweeters.? Start by disengaging the the king stud on the passenger side and work your way back :p
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Now I have full understanding of why your truck is on blocks more than not.......... :laugh:
 
Sorry to hear that this problem has shown it's ugly head again.  It's gota be the pump or the voltage but as to which  ???

 
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