White Smoke

[Sawz]

Finally got the old truck resurected and in good working order, :D got the transmission shifting good,then it quit going into forward gears :rolleyes: But before it did that I would be going about 50 miles per hour or on a grade , lets say under a load. It would feel like it was missing and I would notice white smoke coming out drivers exhaust . Couldnt see the passengers side cuz the mirror wasnt adjust that low. So from what I understand white smoke is atomized unburned fuel versus the black smoke not enough air. Why would it blow white under load, bad fuel?

[catmandoo]

what year old truck and what kinda trans. i know the 700r4 if the lockup doesn't release it will get to chugging this could be what you were experiencing this also could have caused the trans to die

[britannic]

If you have a miss under load, check out these possible causes:

1. Clogged/worn out injector(s)

2. Low compression in some or all cylinders (compression test). Possible causes include worn valve seats, bent valves, worn rings (excessive blowby should be evident), holed pistons, etc.

3. Restriction in fuel return line causing altered timing, incomplete injection.

4. Worn IP (usually the symptoms involve all cylinders at once though).

5. Worn lift pump.

6. Air bleeding into fuel system, preventing random injectors from popping off (massive air leaks usually result in a complete engine shutdown).

7. Faulty electrical connection to IP shutoff solenoid (pink wire) resulting in intermittent 12v feed.

[Sawz]

Its a 83 k2500 700r4 tranny it has new filters fuel, oil and tranny. new fuid in tranny. also a new tank switching valve the old one was leaking through to the other tank on return line sucking fuel out of one tank to the other explains the drop in fuel econoy :eek: new electric fuel pump bypassing old lift pump. we have an emissions test here, it passed with flying colors. just later in the day it started doing this. it will idle smooth and run fine up to about 50 miles per or going up a hill. son switched tanks and said it worked fine although I never got to test it good because the tranny went out before I had a chance ... a side note they do a dyno test for emissions, it was rated at 75 hp at 50 miles an hour at rear wheel seems a bit low to me. they had factory rating of 130 for this year and engine

[Eric Deslauriers]

There is no way they're at WOT on the emissions dyno test. They'd need straps for that.

It's how much hp is required to move your truck at that speed IIRC.

I've never seen them have my vehicles anywhere near WOT. Several of them would have leapt off the dyno (sans straps) and into the brick wall on the other side of the parking lot. Blocks or not.

The #s a SWAG anyways, based on aero data they have.