Forum Discussion

Explorer

Aug 25, 2013

Diesel exhaust smoke

OK so I've got a 2003 Chevy Duramax with about 135 K miles and it now has blue to dark smoke when starting or at idle. I don't see smoke at road speeds unless I really punch it.
So now my question... A RV park owner noticed the exhaust when I pulled in to dump and asked if I had replaced the fuel filter as he noticed the blue exhaust. We have replaced it several times and WONDERING if there is anything like a tune up or other measures that can correct this issue. I get good milage and not other adverse effects with this truck.
I just assumed this is what happens when a truck gets this many miles on it or can this be corrected?
I see the big 18 wheelers who blow smoke so was not too concernend but would like to know if a tune up or something can be done to restore my Chevy to not do the smoke thing. Any thoughts.

Tow Vehicles

13 Replies

powderman426
Explorer
Aug 25, 2013
At 135k it shouldn't smoke. Thats just broke in. Does the dipstick show oil missing?
hmknightnc
Explorer
Aug 25, 2013
Check your exhaust piping, you can get that condition if you have crossover pipe small leak prior to turbo inlet. Don't know if that is your problem but worth a look, especially if your still running on original 10 year old exhaust piping
azdryheat
Explorer
Aug 25, 2013
Don't overlook valve guide seals letting crankcase oil seep into the combustion chamber. I may be wrong in this theory applying to Diesels but that is what we look for in gas motors. I had the blue smoke coming from my gas car and replacing the valve stem seals cured it.