Attention: TDR Forum Junkies 
Need some help troubleshooting a problem with heavier than normal black smoke. My truck is an ’01 with mods as shown in the profile. About a month ago, I was operating at 8000’ elevation, no trailer, light load (maybe 500 lbs in the bed). SMARTY was set to Catcher #5. Turned on the PacBrake to warm up the engine first thing in the morning, just like always. Drove about four blocks to a stop light, then it suddenly started pumping thick black smoke out of the exhaust, and the engine started lugging way down. I quickly turned off the PacBrake and after moving off the side of the road, I emptied the air tank. Thick black smoke stopped and RPMs came back to normal, but the truck continued to emit greater-than-normal amounts of black smoke upon acceleration.
One odd thing about the stoplight incident: as I was slowing for the stoplight, the truck seemed to lunge forward momentarily, sort of like if the accelerator was being depressed at the same time as the brake. But then it stopped. This was just prior to all the black smoke. Not sure what that was or whether it’s related, but thought it worth mentioning.
I considered the possibility of bad fuel, but had filled up at a truck stop about 100 miles previously and everything was working just fine when I had parked for the night. But just to be sure, I drained the fuel filter canister (nothing odd observed). Then after a fresh tank of diesel and stopping for the evening, I changed both the fuel filter and the pre-filter on the FASS. Same issue, no improvement, still getting more black smoke than normal. By this time, I was back down to around 1500’ elevation. I reprogrammed the SMARTY from #5 down to “Stock” and that seemed to help a bit. Eventually reprogrammed again, first to #3 and then back to #5. Still getting more black smoke than normal, and it doesn’t seem to matter whether the PacBrake is engaged or not, or where the SMARTY was set. But at least the super-thick black smoke and engine lugging has not recurred since that one incident.
I did call PacBrake, and they suggested a sticking solenoid might be holding the butterfly valve closed or partially closed. But the actuating cylinder appears to be opening and closing fully when I checked it. Lubed it up again anyway once I got back home.
Also once I got home, I checked out the air filter. Not excessively dirty, but I cleaned and re-oiled it anyway. I’ve run about 7 tanks of fresh fuel through it since then (usually letting it go down to between 1/8 - 1/4 tank before refuel). Have reprogrammed SMARTY back to #5 and it seems to have a bit less power than usual and a bit more smoke. The EGTs and fuel pressure seem normal. I had a trusted diesel mechanic check the boost (I don’t have a gauge for that yet) and he told me that it was in the normal range, although he hadn’t written down the actual reading.
Ever since the problem first occurred, the truck seems to lack the power that it used to have. Still more power using the Catcher SW settings than at Stock, but subjectively it seems less powerful.
So now I’m stumped. Still getting more black smoke than normal, and it seems not to matter whether the PacBrake is on or off, or where the SMARTY is set. There are no codes. Any ideas?
One odd thing about the stoplight incident: as I was slowing for the stoplight, the truck seemed to lunge forward momentarily, sort of like if the accelerator was being depressed at the same time as the brake. But then it stopped. This was just prior to all the black smoke. Not sure what that was or whether it’s related, but thought it worth mentioning.
I considered the possibility of bad fuel, but had filled up at a truck stop about 100 miles previously and everything was working just fine when I had parked for the night. But just to be sure, I drained the fuel filter canister (nothing odd observed). Then after a fresh tank of diesel and stopping for the evening, I changed both the fuel filter and the pre-filter on the FASS. Same issue, no improvement, still getting more black smoke than normal. By this time, I was back down to around 1500’ elevation. I reprogrammed the SMARTY from #5 down to “Stock” and that seemed to help a bit. Eventually reprogrammed again, first to #3 and then back to #5. Still getting more black smoke than normal, and it doesn’t seem to matter whether the PacBrake is engaged or not, or where the SMARTY was set. But at least the super-thick black smoke and engine lugging has not recurred since that one incident.
I did call PacBrake, and they suggested a sticking solenoid might be holding the butterfly valve closed or partially closed. But the actuating cylinder appears to be opening and closing fully when I checked it. Lubed it up again anyway once I got back home.
Also once I got home, I checked out the air filter. Not excessively dirty, but I cleaned and re-oiled it anyway. I’ve run about 7 tanks of fresh fuel through it since then (usually letting it go down to between 1/8 - 1/4 tank before refuel). Have reprogrammed SMARTY back to #5 and it seems to have a bit less power than usual and a bit more smoke. The EGTs and fuel pressure seem normal. I had a trusted diesel mechanic check the boost (I don’t have a gauge for that yet) and he told me that it was in the normal range, although he hadn’t written down the actual reading.
Ever since the problem first occurred, the truck seems to lack the power that it used to have. Still more power using the Catcher SW settings than at Stock, but subjectively it seems less powerful.
So now I’m stumped. Still getting more black smoke than normal, and it seems not to matter whether the PacBrake is on or off, or where the SMARTY is set. There are no codes. Any ideas?
