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

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.

by in Tacoma, WA on April 07, 2013
2 answers 3 comments
ANSWER by , April 07, 2013
have the codes checked if the engine light is out your ecm stores codes and can be found with an obd reader
COMMENT by , April 07, 2013
thanks very much...will do
ANSWER by , April 07, 2013
have it scan tested for codes
COMMENT by , April 07, 2013
yes i will thanks.
COMMENT by , July 15, 2013
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