gamiller31

My truck is stock(except for whats in sig) as far as I know. I purchased it used, so do not know what prev owner may have done. I have also never driven any other 24V truck for comparison. My question is, if it is stock, should I see lots of thick black smoke @WOT and rpm's over 2000? Truck does not smoke at less then 2000 rpm's, but will smoke big time over 2000. I do think my MAP sensor is not quite right, because I disabled the wastegate, and it does not defuel over 22 psi boost. Is this normal?

Thanks in advance for all comments.

Smokee

I don't have a 24V, but I do not think that you should see a LOT of smoke at that RPM. Have you checked all of the intercooler boots, especially the ones at the bottom of the cooler?

gamiller31

I have inspected them, but not actually taken them off or done a leak check, but my boost gauge shows 5-7 psi cruising at 70, and will go to 25 psi @WOT over 2300 rpm's. Is this not a reliable reading?

BigBlue

It doesn't sound like you have a leak. It's funny it won't smoke below 2000rpm's. Diesel's usually smoke more at low rpm due to the lack of boost(air) to burn the fuel.

graphitecumnz

Mine smokes more at low rpm's.

What gear are you running in?? mine will smoke noticeably at those rpm's if I'm running in 2, 3 and 4...

gamiller31

Notice it smoking mostly in 4th and 5th gear, probably would see it in 6th, but by that time going too fast. I usually don't go WOT in 2nd and 3rd(have to shift so soon), just smoothly take it to 2400 rpm, then go WOT in 3rd and 4th. I also figured I sould see it more at low RPM, but don't notice it there. I do have a very noticable turbo lag below 1800 rpm.

RowJ

May or may not be reliable readings on boost. Most big air leaks will result in low boost readings. Small leaks can just cause your turbo to work harder than it should - trying to keep up.
Under this condition you will get higher than normal EGT's. How are yours?
You get no smoke below 1800 rpm?
You mentioned you inspected boots - did you tighten all 9 clamps? If truck is stock would think 25 psi boost is high - might throw a code; have you checked this?
Just fishing here; your smoke at high RPM only is very unusual.
Rowland

gamiller31

My EGT gauge is post turbo, and I have never been able to get the temp over 900 at anytime at WOT, even towing 4000# boat. Crusing at 70, EGT is 550 - 650, depending on wind/hills. These readings seem normal?? I will try WOT in 2nd and 3rd, and try to watch exhast to see if any smoke at all below 2000 rpm. I really want to know if I should see smoke like this at all on a stock truck?

RowJ

Have heard from guys with pre AND post EGT probes that can be as much as 500* difference under heavy load. 900* post could equate to 1400* pre turbo which would be hot, if sustained, for stock engine towing 4000 lbs.
Thought it possible previous owner had installed bigger injectors which will give you extra smoke before spool up in all gears? Bigger injectors would make sense with the Max Flow System, or did you put that in?

gamiller31

I installed Maxflow system. Any way to tell if injectors are not stock?

RowJ

Unfortunately, no easy way. Even if you pull one out - usually no markings. But bigger injectors would smoke more across the board, and especially before turbo spool up, not just at high rpm.

I know there are several Diesel performance shops in Houston area. You might want to find one and have them test drive your truck for their opinion on your smoke problem.
Here is one I have heard or but know nothing about http://www.dieselinnovations.com/
Let us know what you find.

bentwings

My 99 will smoke in 3rd if I wind it up to 2500 + in 2nd then shift to 3rd and tromp on it. The turbo probably isn't spooled up yet and there is over fuel so smoke. It's not big time but enough to dose the ricers occasionally
It will also smoke if crusing at relatively low rpm in a tall gear 4th or 5th and just tromp on it but not as much.

gamiller31

I will probably take it to Mainland Diesel(since they are close to me), and let them drive it, and see if what they think of the performance, and smoke. Will let ya'll know what I find. Thanks to all for the advise.

Steve10

Ironic...I was going to post a thread on this when I got to work this morning. Since the daylight savings time change, I'm in traffic before sunrise and have noticed I can create quite a bit of smoke in the headlights behind me when leaving stoplights. My truck will not smoke hardly any if you're accelerating normal and shifting at 2800 rpm, but once you go past half throttle it can create quite a bit. With the 6spd, once I'm in 3rd and give it about 3/4 throttle it takes off like a jet all of a sudden at ~2300 rpm and kicks the smoke out until I shift. This truck has no shortage of power when driving normal, but when you mash the pedal it really has that set you back in the seat, all of a sudden at that 2300 mark. I bought this truck used and don't know if the previous owner changed injectors. If I can generate smoke like this, does that mean I should be looking for a problem? The truck sure runs like it doesn't have a problem.

killfast1

Mine does the same thing but it kicks in at about 2100 rpm with a cloud of black smoke that will fog out the cars behind me but it does it in any gear when im rompin it. And i love to do that.