With only 3500 miles on the 6.6 TURBO it gave such a LOUD engine knocking, stalling, and jerking (looking in my rear view mirror) a large cloud of BLACK SMOKE trailed. This is my first Diesel truck and must say this S*** is not what I expected out of this truck. The truck is sitting at a GMC dealer now.


Can anyone please shed some light on this and what I can expect. I have no problem torching the thinghttp://www.dieselplace.com/forum/smileys/Evil Smile.gif. Thanks for your help in advance fellow members.


Lorenzo21Edited by: Lorenzo21

Just so you know, the duramax is a 6.6 not a 6.5

Thanks it's been corrected. This is my first Duramaxhttp://www.dieselplace.com/forum/smileys/Approve.gif.

lots of items it could be. ours did the same thing. our issue was the selenoid that controlled the vanes on the variable turbo. caused it to buck, snort, blow smoke, not accelerate etc. It was being starved for air. the point being it doesn't have to be an injector to cause these symptoms. can be but there is other hardware that can do this also


dave

Drcook, did you hear an audible fuel knock when it was happening? Did you get a check engine light? Thanks.

Yes and Yes. As soon as the selenoid went, the check engine light came on. The knocking etc was pronounced when getting into the throttle. at light application, low speeds, ie: "babying the gas pedal" the engine "seemed" ok, but when trying to do any acceleration, it became very apparent there was a problem.


The GM tech that was dealing with our dealership service tech told them that the selenoid usually will go within the first 1000 - 1500 miles, ours made it to 1200. just like any elecro-mechanical device, this short time frame holds true. I build computers on the side, and if a part is going to go, it usually goes within the 1st 30 days. then they seem to hold together for a while.....

Thanks for the response. So far I've seen a few with no check engine lights on but with fuel knock and black smoke. Turned out to be injector stuck.

Oh we see the signs of the lly............................................... .................................................. .......................

I seem to have something similar happening, but it's worse when Cruise control is on. Does anyone know of a connection between the two?


I don't have any warning lights on - even when it's knocking, spewing black smoke, white smoke (when the knocking/clacking gets bad), and producing low power -especially above 60 mph. But, the funy thing is, I get this mainly when the cruise is on.


When I turn off the cruise, and "pedal" it lightly, I can go up to 75 mph with some smoke, but nothing like with cruise. Then to test my theory, I slowed down to 65, and applied the cruise. Almost immediately I get the smoke, clacking, and power loss occur. When I turned the cruise off, it continued to smoke badly for about 30 seconds. Then it smoked less (but still much more than usual) but didn't produce any of the other effects (knocking, clacking, white smoke).


Oh, I have 2601 miles on the truck.


Any ideas anyone?


Thanks.

Dear GUFFID,





I recently took my truck in for the identical problem into the dealership. They stated having cleaned a air flow sensor and recalibrated/programmed the air flow. This took care of the problem immediately. It took approximately 30 minutes at the dealer to fix.


Let me know what happens to yours.





Good Luck,


Lorenzo