I have a '99 SE-L with 35,xxx miles. For the second time I have taken the following codes: 0707, 0510, & 0304.

0707: Knock Sensor
0510: Undefined
0304: Rear Heated 02 Sensor

The CEL came on for the first time in late October after I filled up with Shell premium. I had never used Shell before in the car, but it was the only gas station available at the time. I checked and reset the CEL, and I ran Sea Foam and Berryman's through the tank. I have filled up with two new tanks of Exxon premium, and roughly 800 miles have been driven.

No problems until yesterday. The car runs like a scalded cat.

Am I dealing with two distinct issues that need fixing? Could it be that fixing one issue will take care of the other(s)? Do I have issues attributed to the Shell gas? I have reviewed the sticky concerning the CEL and codes, and I would simply like to know what to tackle first.

Your help is appreciated.

James

 

Running fuel treatments will not fix any of the problems.

I would replace the knock sensor first. You should notice immediate benefits in performance and fuel mileage.

 

WHAT HE SAID