Paul Walker Crash Investigation Ongoing -- Report Blaming Speed Alone Is Bogus

A new report blaming Paul Walker's fatal car accident on excess speed alone is false -- multiple informed law enforcement sources tell TMZ.

The Associated Press is running a story that investigators have already concluded there was NO EVIDENCE Paul's Porsche had mechanical problems at the time of the crash.

According to the report, investigators believe Paul's friend Roger Rodas was simply driving way too fast ... and that's what led to the November 30 crash in Santa Clarita, which killed both Walker and Rodas. The report says the investigation also ruled out debris in the road as a possible cause for the car losing control.

But we've learned that's not true -- multiple law enforcement sources familiar with the investigation tell us, the investigation is ongoing and NO determinations have been made regarding the cause.

We broke the story ... the L.A. County Sheriff's Dept. has summoned Porsche engineers from Germany to come here and examine what's left of the engine, brakes and tires in an effort to determine the cause of the accident.