Had the O2 and ks code. Changed both upstream O2 sensors cleared codes. Gas mpg still sucks. Check engine light has not come back on. Checked codes again and ks only code still there. Will a bad ks kill my mpg?

On my air vents, the driver and passenger side vents blow great, on the 2 middle vents the one to the right blows great but the left one barley blows at all. Any ideas?

 

From what people have stated on here, yes, the ks will decrease your mpg. I just changed mine and am on the first tank of gas, so can't confirm.

 

^exactly the same here..changed it on saturday then filled up..

 

Yes it will kill MPG and HP, but it will not set a CEL.

 

i just changed my ks about a month and half ago and i have seen in the range of a 5-6mpg difference with the new one, along with better throttle response. the ks code is a ghost code most of the time, easiest way to tell is take yours off(look for pmodr's youtubes) and if its still in good shape (no cracks or melting) then its something else wrong but to answer your question. YES a bad ks will affect your mpg.

 

There is a screen behind the outlets, shine a flashlight in there and you will see it. Maybe it has gotten plugged with dirt on the one side.

 

I would think if you are not using premium gas, yes. knock sensor kicks in only if there is an engine knock. Without it, your engine will continue to knock and you would have bigger problems to worry about. Piston slapping is a serious business, this can take out your engine.

 

I been using the regular 87. Today I switched to and will stay with 93 premium from shell.

 

With a bad sensor or no sensor at all, the ECU will automatically retard the ignition timing fully. In this mode there will be no knock.

Two separate conditions. Spark knock is the preignition of the air/fuel mix and the resulting explosion of two flame fronts colliding. Piston slap is a worn piston in a loose bore slapping its skirts on the cylinder wall.

BTW, with a bad or no KS, you could run regular and never knock.

 

Not necessarily. My KS was tripping the code & when I changed it, the old one looked great- no cracks, melting, corrosion, etc. But the new one cleared the code & I'm getting better gas mileage.

 

-Usually the KS will follow another code, hence ghost code, doesn't mean the ks is good in all cases, which is why after you've taken care of the bigger problems, if a KS code still appears then you do have a bad KS

-Look at asand1's post, that is the correct answer.

Always use premium. IMO

 

Now I have the P1440 code Evap control system small leak.

 

Make sure the gas cap is tight and not damaged for the evap, the knock sensor is one thing that will effect gas mileage but also tire pressure, make sure it's good especially if you haven't added much during the summer. Stay up with your oil changes and spark plug change intervals too.

 

My point was just that "no visual damage" does not mean the KS is good. If a KS is dropped prior to installation, it can be damaged. The FSM even says not to install a KS that has been dropped.