Date: 202108
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower ZZZ
Aircraft component: Air Conditioning Distribution Ducting; Clamps; Connectors
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Other / Unknown
Second reporter function: Pilot Flying; Captain
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Person Flight Crew
When detected: Other Takoff roll
Result: Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Rejected Takeoff; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Gate; General Flight Cancelled / Delayed
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: Captain (CA) & First Officer (FO) commented on a dirty sock smell on taxi out; no other abnormal indications. Upon adding takeoff power; left side of cockpit filled with a smokey/steamy mixture and acrid smell. Captain rejected. Maintenance (MX) advised there was an engine wash performed night prior and the aircraft engines were not run up properly after the procedure. We ended up having MX onboard for the runup who had us perform duties from a checklist that should have followed this engine wash including a run up of at least 5 min at 70% N1. The odors were still present during this time. If MX had been performed accurately the night prior; this could have been avoided. And; unfortunately; this routine wash is performed under a 'work card' making it invisible to pilots during a preflight in any MX accounting systems or via the aircraft logbook.


Second narrative: At approximately 90 KIAS; smoke came out of cockpit floor; under Captain's side; and rejected takeoff. Uneventful. Cleared off runway stopped and had emergency equipment check for fire. All clear and taxied to gate. Maintenance said engine wash were performed overnight; probable cause of smoke/steam on takeoff roll. Maintenance did a high power engine run; delayed flight and re dispatched after maintenance cleared aircraft. Maintenance crew did an engine run; at gate; versus high power one the night prior.  According to mechanic; a duct clamp was installed improperly in the E&E bay; residual water and duct clamp coming off on ducting might have contributed to what appeared to be smoke/fumes/vapor on takeoff roll after takeoff power was applied. [Reporter recommends Maintenance] perform high power engine run after every engine wash. If non-high power engine run; performed by maintenance overnight (info only entry to AML should be recorded so as to keep flight crews informed).


Synopsis: B737-800 flight crew reported smoke and fumes emanating from left side of the cockpit during takeoff roll. Flight crew executed a rejected takeoff and maintenance was requested.