my poor truck is breaking... help please

[tybardy]

This morning I fired my truck up and it stalled out... fired her up again and she idled like sh*t and I had to keep feathering the gas. Engine light fired up and stayed on the entire way to work. At every stop light she would idle like a hog and I had to keep floating the gas to keep her even.

get to work and borrow the guys code reader and the engine light was off and no codes were present. Luckily it was a nice reader and showed the back logged codes....

mass air flow sensor.... something or another

fuel bank 1 - lean condition

fuel bank 2 - lean condition


Its running fine now.

It was 22 degrees outside when i fired up the hoe... that had to play a part in this, but obviously it shouldnt...

any thoughts on what is going wrong and what I can do to repair it?

 

[UofMZ71]

i just helped a friend with the nearly exact same problem in his bmw.

His car broke down in nashville and i went up there and trailered it back, because the shop he had it towed to was going to charge $1700 for repairs which included:

(2) o2 sensors
spark plugs
fuel filter
an air flow flap
+ labor

we towed it back and replaced all of it for $800 and about 3 hours time (minus the air flow flap) but did come to find out it was the fuel PUMP.

So if anything i would check your pump and your filter. Just a thought

 

[tybardy]

fuel pump was my very first guess.... the filter is relativly new, the spark plugs are almost brand new, the entire intake system shouldn't be the problem as it is a short ram and the MAF is very well taken care of. I have a K&N but it shouldnt be oil on the maf as i have not oiled it in a very very long time and i have cleaned the MAF.

Any idea how to actually "check" the fuel pump
?

 

[VikingFan]

I agree, if both banks are lean I would check fuel pressure (i.e. Pump and filter) first. If it got down to 22* are you sure you didn't have any water in your fuel that could have frozen? Might want to try some Heet in the next fill up too.

 

[tybardy]

what is heet? i "shouldn't" have water in the fuel tank... i sure as f*ck hope not at least.

 

[UofMZ71]

fuel pump was my very first guess.... the filter is relativly new, the spark plugs are almost brand new, the entire intake system shouldn't be the problem as it is a short ram and the MAF is very well taken care of. I have a K&N but it shouldnt be oil on the maf as i have not oiled it in a very very long time and i have cleaned the MAF.

Any idea how to actually "check" the fuel pump
?

yeah there should be a way to check it, or there was in his bmw. (this is what we did) There is a nozzle on the fuel rail, unscrew the cap and stick a screwdriver down to press the little needle inside (like your tire valve), if it shoots out gas then your ok, if its air or a mix then you may have to replace (make sure your car is in the "accessory mode" or whatever you wanna call it - key in but car not on)

 

[tybardy]

gas doesnt freez at 22* (right?)

its running perfectly fine now that the sun is up and its warmer

---------- Post added at 12:29 PM ---------- Previous post was at 12:23 PM ----------

hypothetically.... if my fuel pump is giving out... why would the extreme cold accelerate the symptoms? As I mentioned, it purrs like a kitten right now

 

[k9lovr]

I was thinking the same thing when it comes to water in the tank....no gas does not freeze at 22 but water does. Some fuel pumps get noisier when they are starting to go bad as well. Louder whine than usual will come from them.

 

[UofMZ71]

if it is the water issue, maybe condensation is building up then freezing, that could be my only guess as to that.

now on another hand, since it was cold and your pump may be going bad, then those two combined created an issue, then when the truck ran for a while and warmed up, it temporarily fixed it.

But with my friends beemer, his service light was on for maybe 3 weeks until it finally just wouldnt work anymore. On and off with sputtering then running fine... then dead...

 

[OklabyGodhoma]

What you described sounded exactly like water in the fuel....remember water is heavier and goes to the bottom where it is quickly picked up by the siphon line. Even small amounts can give the symptoms you described and even gave a stronger "feel" since you say that as the day got warmer it cleared completely. Heet will help to dispel any condensation in the tank. Also if it were a larger amount of water you still would not be running. Condensation can come from fuel you recently pumped or even more common is a cracked or worn out fuel cap gasket.