what happens if regular gas has been used instead of premium in a mazda cx-7?
The knock sensor will retard the timing. Reduced performance and lower gas mileage will result. Use of regular gas once in a while won’t hurt anything. Long term use of regular could result in internal engine damage.
thank you for your answer. i am considering buying a used 07 mazda cx-7 and am concerned about how i’ll be able to tell if regular gas was used regularly. can you suggest anything?
If this vehicle is going to be purchased from a private party, simply ask, “What type of gas do I need to put in this vehicle?”. If they have been cheaping out, they may just feel like bragging that they have run it on regular gas “without any problem”.
The seller may feel that he/she is giving you a good reason for buying the vehicle, when, in reality, they are providing a very good reason to avoid it. Of course, the second owner is the one who is likely to have a problem from the build-up of carbon deposits in the cylinders.
its from a dealership. the salesman did say 'it doesnt matter if you use regular’
but, in fact, it does. i was hoping there might be a diagnostic test or something that would clearly indicate if the wrong gas was used for a long period of time.
Unless someone volunteers the information I’m not aware of any way to tell what grade of gasoline has been used.
Salespersons will say ANYTHING. Don’t believe it. It does matter and if you buy the vehicle you will have to feed it premium gas.
As mcparadise implied, DO NOT believe anything that a car salesperson tells you. Between outright dishonesty and being very poorly informed (even about new cars that they are selling), little if anything that they tell you can be counted on to be accurate.
The 07s are known for some problems in their early builds.
http://www.mcx7.com has most of the info on the 07 problems
As good a vehicle as the CX-7 is, I just have an aversion to used turbos…