Hi All, I recently purchased a 4WD 2500 24v 5.9 with 115K miles. No problems at all for the first 800 miles. Twice since then, the engine has stumbled. Cruising at about 35mph, fully warmed up, with about half a tank of fuel, it just fell on its face for about a half a second, and then picked itself up like nothing ever happened. Any thoughts? I drained some clean fuel from the fuel/water separater, no water. There was a wire dangling that I re-connected to the filter housing. I think it was for the water in fuel sensor. That was about 100 miles ago. Today, the ABS and BRAKE lights come on and stay on. Gauges all look normal, and the brakes seem to work fine. Probably unrelated, but pressure builds up in the fuel tank. Is that normal? I was going to check fuel pressure at the filter. My fuel pressure test gauge goes up to 100 psi and says DO NOT USE ON DIESEL OR MULTIFUEL ENGINES. Why? Possible gasoline contamination of fuel? Who knows, I'll buy a new gauge, any suggestions? Thanks,Jay

Update on the fuel tank pressure issue, its was actually negative pressure. I had previously cleared some dirt from the rollover valve/vent tube. After loosening the fill cap, I blew 60 psi air in through the vent, still no joy. It took 100 psi to dislodge whatever was stuck in there. Tank vents properly now.

P0216 code that you posted earlier is basically the failure of the timing advance cam inside the pump and the pump can no longer advance timing properly. So basically the timing is stuck in full retard position most times. White smoke in the mornings, low MPG, low power... This is all cause from low fuel pressure. When the pressure starts to fall below 10 PSI the VP44 starts taking on damage. Kiund of like letting the engine oil pressure fall to low the bearing don't have enough to keep the part floating on the thin film of oil and cool thing properly. Well the VP44 is design the same way you have low fuel pressure there isn't enough fuel to cool and lube the pump so part start wearing out. Sorry for the bad news... But the replace of the VP44 is rather easy and can be done with basic tools... The only special tool you need is a gear puller... You can use a damper puller or steering wheel puller too.

White smoke in the mornings, low MPG, low power...

I haven't seen any smoke in the mornings, haven't calculated MPG yet, and don't really know if its suffering from low power. It does have more power than my old suburban (350 gasser). I been looking for 0-60 mph times to compare to, or some other way to confirm power loss. Any ideas?

Well MPG would be the easiest to find out... Typical stock it rolls in at about 16-17 MPG... Modified it should hit about 19-20 MPG... Or better...

Well MPG would be the easiest to find out... Typical stock it rolls in at about 16-17 MPG... Modified it should hit about 19-20 MPG... Or better... [ATTACH=CONFIG]460[/ATTACH]

You racing people all the time? The ratio between your above 20 to below 20 mileages is the same ratio as me, cept the opposite

Edited January 19, 201015 yr by ISX

Depends if I drive the highways to and from towns or go up in the mountain gather firewood... When on the pavement doing long haul is when I hit 20-21 but when I'm on the dirt road I can just forget about it... Climbing 25 miles from 1,800 feet elevation to 7,500 or 9,900 max elevation tends to eat fuel.... I don't see much over about 6-8 MPG on the SG II display... (Ugh!)

Climbing 25 miles from 1,800 feet elevation to 7,500 or 9,900 max elevation tends to eat fuel.... I don't see much over about 6-8 MPG on the SG II display... (Ugh!)

it makes me laugh thinking about what it would say if it was the 8.0L....

it makes me laugh thinking about what it would say if it was the 8.0L....

Well just playing I've seen a few time at 0.00 MPG displayed and watch the Today's MPG and the Total MPG fall like rocks off a cliff... :shocked2:

it makes me laugh thinking about what it would say if it was the 8.0L....

I had a 99 long box qc 4X4 with 3.54 and auto with the 8.0 V10 and I averaged 9.5 mpg overall, I saw 11mpg 1 time in 2 years, 55 mph for 200 miles to get it. I ditched it for my 02 cummins which in hind site was dumb also because i COULD HAVE GOTTEN AN 03 cummins for the same price with only 5k more miles but I liked the look of the 2nd gen better and was leary of a first year 3rd gen. My best friend ended up with the 03 and it has been flawless for him.:bang: Win some loose some.