[pkhona]

Hi Gurus,

Does the brand matter. I know this has been discussed before - but seems to have lost that thread.

Yesterday I filled up with Valero's 91 and pick-up seems to have degraded to noticeable level. Also when I accelerate , it takes more time ?Will this cause problem in my engine, is it advisable to replace the fuel ?

I have observed that Chevron and 76 give the best perf. Could I be biased or is it real ?

Regards,

pkhona

 

[Enforcer]

Touched on it in This thread.

There was a large discussion on this at one of the Z forums.

Outside of Shells claim of better gas mileage :bsflag: they all are required by law to have certain anti-fouling capabilities, although all of them claim to be better.

The refining process for all but Amoco was purported to be the same. I don't remember the details, but Amoco was unique.

Before I read that stuff, Amoco was and still is my fav.

But for 91+ octane, it can also depend on where you buy it. Purportedly, the oxidizing additives (octane boost) are mixed at the stores in a lot of cases.

 

[pkhona]

Hi,

Thanks for the info. Looks like valero's 91 has some additivites which is not being liked by car. In fact I had tried valero on my altima also and same effect was observed. I had taken it lightly at that time since that car was very old.

Do I pump out the fuel from the tank and put good one ? or one time will not effect the knock sensors to retard the engine permanently ?

Regards,

pkhona

 

[stonemaster]

I had a Honda Prelude before my Mo and it required premium (91+). It was even clearly marked on the speedometer and on the filler door (in BIG LETTERS) by Honda, "USE PREMIUM FUEL ONLY". Once, a garage mechanic had to fill my tank after a repair service and put in regular grade. I didn't know that and thought he did something to my car since it was performing poorly. I found out about the gas (you should have heard me yell... I guess the moron couldn't read). So when the tank was half full, I filled it back up with premium to bring up the octane a little. Then I let it go until the fuel light came on. It was fine after that once I got back on premium. I'm thinking your Mo should be the same. The knock sensor and O2 sensor should detect the higher octane and compensate. If not, then I would get it looked at. (I also learned that disconnecting the battery on my Honda resets the engine computer so that any previously 'learned' settings for the engine got reset. That actually helped kick the performance back up after the gas incident. Don't know if that will work on a Mo, but it worked on a friend's Nissan Maxima. )

 

[Enforcer]

Yeah, disconnect negative terminal of battery for 5 minutes and the fuel maps will reset.

But it's really not necessary. The ECU is constantly learning new profiles, on the order of 20 minutes of driving all effects should be neutralized.

Pk, you don't have anything to worry about. Just don't buy it again.