Temps have been up in MI here over the past couple of weeks which leads me to a question. I have noticed under acceleration till engine get up to higher RPM truck blows heavy black smoke. It does not happen when temps are cool. My first thought is its the ECU's fail safe of reading high IAT's and dumping more fuel to keep cool. Am I right. Truck runs fine and as RPM's increase accellerates quicker and black smoke goes away.

Can you determine about what boost the black smoke quits at?

The optic bump will increase overall fuel delivery quantity, and advance your timing a touch, both will give you a little more black smoke.

From your description, it sounds like your turbo is slow to build boost, and that could be for a variety of reasons, failing WG solenoid, leaking vacuum line/pot, weak vacuum pump, worn compressor wheel in turbo, restriction in air filter, etc...

I'll make sure to watch boost to see when black smoke goes away. But I've covered some of the other possibilities. New air filter (AC Delco in stock box format), turbo is brand new, and by the way it whistles it doesn't seem to be bogging down to build boost pressure. I'm leaning toward either WG failing, or vacum pump.

Just did vacuum pump on my 3500HD and changed the wastegate and( turbo boost sensor?) Not sure what it is but dealership charged me to put it on.Both trucks had similar symptoms like your having.

Well isn't that perculiar, I got a boost sensor code about a month ago, but haven't gotten anything since then execpt this $*#*$&#)* temp code. Something about have a faulty reading or mixture problem or some other crap. I have done and change everything I know of execpt thermostats. It appears that's next.

I started noticing the same thing in my truck about a month ago.If I sit at a light for any length of time...as soon as the light turns green and I hit the pedal, The truck seems to lack power for a couple of seconds and DUMPS black smoke on the poor little Ford Escort sitting next to me with his windows down. After that..it seems to run fine till I get to the next light...at which point the Ford Escort is now in front of me.(with soot all over his face)

Well let's add the newest find. Yesterday was doing the usual SOOT Displacement and I thru and engine code P0236 which is a faulty reading from Boost Sensor. I'm going to look around on here right now but was wondering if you guys could point me in the right direction to fix this.

Normally its not the actual boost sensor. The code is boost sensor out of range, meaning, the turbo isn't making the boost pressure the PCM expects that it should be at a particular load. And with black smoke, I'd be leaning towards low boost.

Did the temp code read something like 'insufficient coolant temp to maintain stable operation'? I would definitely start with replacing the T-stats then. They are semi prone to suck the rubber o-ring underneath them preventing the stat from closing and keeping your engine from getting as hot as it should.

As for your boost problems, I would start with checking all the vacuum lines very carefully, and the solenoid is too cheap and easy to replace not to try.

TDG


It appears you have finally directed me in the right direction on the coolant code. My engine definetly does not heat up to where it is supposed to be, execpt on these extremely hot days. But normally I can't get the thing to heat up at all, and in the winter, that's another story, if I get it to budge off the 160 mark it's a miracle. Some would be very happy with that, I just want it to work correctly.

I'm going thru the vacuum lines right now. But where is the boost solenoid? And where do I get one, all the local parts places can't find a replacement in any of there books.

Dealership is probably best place to get a new Wastegate solenoid. Should be only about $30. If you still have the 'Turbo Power' cover, it will be at the back driverside corner, on top of the valve cover near the firewall. Two plastic lines into it, one orange from the vacuum pump, and one black to the WG actuator.