My truck was built March 2004- i'm guessing that makes it 2004.5. Anyway it normally runs great but a couple weeks ago I was passing somebody on the freeway and at 95 mph it stopped accelerating and started choking out a lot of very black smoke. Then it wouldn't let me get over 65mph. Runs fine at 60mph but not faster. I pulled over and shut down for a minute and then it seemed fine but I didn't try to exceed 90mph with it again. Then the other day it did the same thing except now it does it at 75 mph- coughing out lots of black smoke and won't go any faster. The truck has less than 135,000 miles on it. It has used about 1.5 pint of oil in the last 600 miles (unusual for this truck) and the oil appears very dirty. Oil change was done 2500 miles ago. It starts the same as always and runs about the same as always but really gives me trouble when I am trying to pass somebody. Truck is never been abused and never been modified in any way. If anybody has run into similar problems please let me know. I can't afford to take it to the *********** (dealer). 2004.5 slt, quadcab, 4x4, 6spd manual

 

Try cleaning/replace the air filter???
Possibly a boost leak...

 

Yes, it is an 04.5. Do you have any codes?

https://www.dieseltruckresource.com/...s-t224833.html

What is your fuel pressure? Do you have a rail pressure gauge?

Have you changed your stock fuel pump on the canister to an aftermarket or the in tank OEM?

 

Thanks for responding. There does not seem to be any code coming up. I don't have a rail pressure guage. The OEM pump in the tank was replaced about 2.5 years ago.

 

Do you have a fuel pressure gauge?

When you do the key trick, does the odometer flash 'done'? Sometimes you have to turn the key 4 times before it displays something.

 

When you start from a standing stop, do you just ease on it?

Go out there and punch it from a dead stop, see if you have the same problem.

If you do, it's an air problem. Could be a plugged air filter, turbo going out, wategate stuck open,blown intercooler boot, busted intercooler, intake horn loose...
Oil level is not high, so you don't have an injector hanging open.

I'm kind of feeling either a fueling issue (not enough fuel under heavy throttle to light the turbo) or an air issue.

 

OK I wasn't checking the codes properly. Codes are as follows 67 37
AC 02
67, AC, and 02 are all relatively minor problems but I could not find what code 37 means. Can you help? I always ease into it from a dead stop because of the standard transmission. (Electronic fuel feed) I treat it like my Freightliner and never touch the throttle on take-off. I checked all the intercooler connections and they all seem tight but even though the truck normally runs fine-it doesn't have the power that it should have. I used to have an '02 equipped with same trans and it had way more power. I'll have to look into some of these other possibilities-how would I know if the turbo is going out or if the intercooler is busted.( I already looked for a crack in the intercooler but could not see one.)

 

You should get a code that looks like this. Pxxxx where the x's are numbers.

 

Don't hold the trip reset when you do it.