Tesla shares have surged 12 percent in the last week, but one equity strategist sees trouble on the horizon.



The stock has risen for three-straight sessions on a slew of news the market appeared to like: CEO Elon Musk said last week the electric car manufacturer was working toward custom artificial intelligence hardware and PepsiCo said Monday it had reserved a fleet of 100 Tesla Semi trucks.



Despite the rally, Matt Maley of Miller Tabak has reservations for the stock heading into 2018. Here are his reasons why.



• Tesla continues to see production problems related to its Model 3, as Miller Tabak's research partners at Cascend Securities point out. This means if someone has not already ordered a Model 3, it may not arrive until 2019. This would in turn allow other auto companies to play catch-up.



• Tesla is also going to have to issue more debt in 2018. This may not prove to be a major long-term concern, but a lot of what investors are getting in shares of Tesla is long-term oriented.



• If the broader market sees meaningful weakness in 2018, Tesla would likely become quite vulnerable. If the stock market sees a correction, investors might be more comfortable holding shares of a company that have more solid immediate- to long-term profits, thus prompting profit-taking in the stock.



• The key level to watch in Tesla, if weakness becomes apparent later this month or in early 2018, is the $290 mark. This is the level at which Tesla shares bounced several times this year. Furthermore, it was the stock's high back in 2014. Once this was broken to the upside last spring, the stock rallied meaningfully. This may be a case of the old technical analysis adage, "Old resistance becomes new support." If $290 is broken to the downside in any meaningful way, this would be quite negative on a technical basis.

Bottom line: Tesla stock has risen meaningfully over the past week, but Maley sees trouble ahead.