Q: Rich run, bad start, sometimes white smoke

asked by on October 13, 2016

Hi, i have deleted DPF and EGR (EGR blank plated and disabled by ecu) after all this problems came. engine rebuild for excessive oil consumption. Car starts bad, sometime smokes white not huge. small black smoke every acceleration. transmission jerking during up and down shift from 1-2-3 and 3-2-1. what can be the reason of problem.

when the car diaqnosed by star diagnostic tool it showed that everything is ok but MASS Air Flow sensor is calculating less air. no error code.

My car has 150000 miles.
My car has an automatic transmission.

The white smoke is a bit worrisome - usually an indicator of a blown headgasket, which will also cause rough running, especially at low speeds from a compression imbalance. The throttle position sensor may also be sending "off" signals to engine management, resulting in a bit of a rich mix, and harsher shifting.

To avoid any unnecessary repairs, I would recommend having a certified technician, like one from YourMechanic, diagnose your shaking/vibrating condition to confirm there is a problem, get an accurate assessment of damage and cost estimate for repairs. YourMechanic can dispatch a mobile, professional mechanic to your location for this repair.

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