For a stock truck...

If I gun it at higher RPM's, I can get a fair amount of black smoke.

The truck is, as far as I know, basically stock engine wise.

It can be a little excessive if you are towing a heavy trailer or something up a hill. Seems like a lot of smoke for a stock truck, BUT it is only at high RPMs with lots of throttle, and otherwise it runs excellently, and gets good fuel economy.

 

Just a thought but how clean is your air filter?

 

High Rpms will get some smoke out of the stock 97. Typically runs over 2600 Rpm will get the truck to the wastegate setting and will continue to fuel for peak HP. This will produce some smoke. Now large amounts of unclear smoke may be an indicator of late timing or plugged air/exhaust components.

 

I think I may have found (part of) the problem. My batteries crapped out on me today, and while changing them, I saw that one of the exhaust manifold gaskets has migrated.

On closer inspection, I have two blown exhaust manifold gaskets. DUH. They aren't super blown (like there isn't soot all over the engine), but it is clear exhaust gases have been leaking.

One seemed to slide forward (a lot... weird), so it is perhaps blocking the manifold passageway as well - the leak and blockage would reduce the power in the flow available to drive the turbo, and explain a lack of sufficient air to burn all the fuel. I'm just thinking it may have been this way for 1.5+ years!!!

2 gaskets @ $6.xx each... I'll install them on the weekend then see.

If they black smoke a bit anyway, what can be done to diminish this/eliminate it (a little more boost?)

 

my truck has no smoke, theres a smoke screw on the back of the AFC u can adjust, and also the starwheel that can affect fuel/smoke.

 

No smoke means no fun

 

well, once I get this 5spd trans in, alittle smoke will be in my future.

 

As ive said before

thats how it starts... U may as well swap in a 215 pump and have some real fun too...

Rick

 

I'll have to hold myself back, because once that first mod gets done, it's all over lol. Especially when theres people like Rick with 1000+tq hanging around here, lol.

 

I got the failed gaskets replaced...



A BIG improvement on the smoke side (feels like better performance too, but that may just be my "know-o-meter" letting me know that if the fuel is being more fully burnt, it has to be putting down more power.

There is still a dusting of smoke as it accelerates at WOT 3rd gear to redline. Probably fine, I'll make up my mind when I can have a chance to let the turbo catch up (pull a big trailer).

For now, she's all good.

Edit: Oh, and I didn't bend either of them after taking them off... I know, shame on me for not noticing it for so long.

 

Wow, the right gasket is totally distorted.. That may help out a tad on exhaust flow.