My 1998 RX300 gives codes p0300, p0301, p0303, p0305, p171, and p172. What is the cause?

Question

what is the issue when i get the combined codes p0300, p0301, p0303, p0305, p0171, p0172,
on my 1998 Lexus RX300

Answer 1

for the misfire codes I would start by replacing the spark plugs with the correct spark plugs (dont use cheap ones)

Both  sets of codes are related

 

P0171 and p0172 could also be for a misfire

Answer 2

P0300 Lexus Code - Random Cylinder Misfire Condition
Read more: https://www.autocodes.com/p0300_lexus.html

P0171 Lexus Code - Fuel Trim System Too Lean Bank 1
Read more: https://www.autocodes.com/p0171_lexus.html

P0172 Lexus Code - Fuel Trim System Too Rich Bank 1
Read more: https://www.autocodes.com/p0172_lexus.html