1996 Toyota RAV4 Q&A

1996 Toyota RAV4 Question: i have a toyota rav 4 2007. check engine light VSC AND 4X4 lights came on .

After 2 days the lights went off on their own.Since then car been fine apart from on odd occasion when going up or downhill a grey smoke comes from the exhaust.Then clears after a few seconds , no loss of power.....any ideas please for this non mechanical Englishman...thanks. -
Answer 1
have the codes checked if the engine light is out your ecm stores codes and can be found with an obd reader -
Comment 1
thanks very much...will do -
Answer 2
have it scan tested for codes -
Comment 1
yes i will thanks. -
Comment 2
I had the same problem on my 2007 Rav 4. The cause was just a loose gas cap. If it isn't closed properly or the senor is broken, those 3 lights will go on. I simply opened the gas tank, took out the cap then snugly replaced and voila the lights went off. I was able to do this and I am a Chic! Easy -