Gas quality - knock issue

[richf]

Hi:

I apologize in advance for posting about an issue that's probably been gone over. I have a 2004, auto tranny, 22,000 miles. I noticed some knock under hard acceleration. I had the car scanned ( harness hooked up at O2 sensors) and the knock levels under WOT were almost off the chart. I've been using Valero 93 octane (mostly because of proximity to my home.) I was told that this gas is horrible, and to use something like Mobil or Shell.. (Top Tier) Could this simple fix really help get rid of the knock issues? I'm also changing plugs and wires due to age, even though everything "looks" good. Thanks so much!

[ALMSGT1]

The knock could be from an accumulation of carbon in the engine. You could add a can of BG44K to a tank of fuel and determine if that eliminates or reduces the problem. I purchased BG44K on Ebay. Good luck.

[LLC5]

Originally Posted by richf

Hi:

I apologize in advance for posting about an issue that's probably been gone over. I have a 2004, auto tranny, 22,000 miles. I noticed some knock under hard acceleration. I had the car scanned ( harness hooked up at O2 sensors) and the knock levels under WOT were almost off the chart. I've been using Valero 93 octane (mostly because of proximity to my home.) I was told that this gas is horrible, and to use something like Mobil or Shell.. (Top Tier) Could this simple fix really help get rid of the knock issues? I'm also changing plugs and wires due to age, even though everything "looks" good. Thanks so much!

The problem is more than likely carbon build up on the pistons and intake valves and possibly restricted injectors. Try running two cans of BG44K through two seperate full to empty tanks of fuel without diluting the mixtures. Always use Top Tier fuels. Good luck with it.

[richf]

Ok - Thanks guys; I'll try it !

[LLC5]

Ebay is a good source for BG44K as stated above. I would also recommend the yellow funnel that attaches to the can to pour into the tank as it is inexpensive and very handy, but a little flimsy. I would buy two if you do purchase one, as I have already cracked two of them myself.

[Jay Guthrie]

Rich, same problem, same gas, same advice try BG44K. I have not gotten around to trying this stuff so if you get some let me know if it works. Say hello to Marty!

[richf]

Hi again:

I changed plugs (GM correct part number) and wires, dumped BG44K into tanks of Shell 93 Octane V-Power. I am not yet through my second tank though. Car still pings under hard acceleration. Could it be the knock sensor? Help... Thanks

[Jay Guthrie]

Rich,
I was able to add the BG44K today with a new tank of Hess 93. It is to soon to tell if it is going to have the desired effect. I will let you know. How are you making out after your second tank?

[richf]

Hi Jay;
I have not been able to take the car out since my last post, but may go to PA with the 'Vette this Sunday - that ought to go through some gas- I'll let you know :-)

[stevebz06]

How is your oil consumption? Oil in the combustion chamber will the chances of knock happening.