Kendra Sunderland may want to tell her friends to slow down … cops in Texas say a speeding car led to her arrest … after an officer says he saw a THC vape in her lap when the car was pulled over.

TMZ’s obtained legal documents detailing the lead-up to the porn star’s arrest … with an officer saying a white 4-door Lexus came to his attention when he spotted it driving over the speed limit.

He claims he checked the license plate and discovered the car had expired tags, at which point he pulled the vehicle over. The officer says that’s when he noticed a THC vape pen on Kendra’s lap — she was sitting in the passenger seat — and asked for her ID.

The officer says he ran her name through the system and found Kendra had previously been arrested for possessing large amounts of narcotics in California. No further details about that arrest are disclosed in the report.

BTW … Kendra didn’t say much to cops, according to the report — but, the officer says she did remind him to read her her Miranda Rights.

TMZ broke the story … Kendra was arrested in August for possessing about a gram of cannabis — well within the legal limit in most states … but a problem in Texas where the drug’s still illegal.

We talked to Kendra right after the arrest, and she told us “I’ve been advised not to say anything. I’m not trying to incriminate myself any further. I just know that I’m not a criminal. I’m just a stoner.”