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I think I got a bad tank of gas.....

Random large amounts knock at varying degrees of throttle, sometimes light, sometimes heavy. I'll just be cruising and look down to a full knock gauge, I'll let off and it will subside just to come back once I start on the throttle again. Other times I can drive without incident.

This just started happening yesterday, the morning after putting half a tank in at Safeway. I've been hearing scattered reports of bad gas around CO, sounds right?
 

ktmrider

Well-known member
Joined
Sep 10, 2007
Messages
3,128
Location
Tempe, AZ
Yeah, good bet it's the gas.
We had an "oh heck" moment in ABQ a few months back, distributor mixed diesel and petrol by accident! Just in case get/save your receipt in the event it was a systematic fuel issue.
 

Running a Magnaflow cat, which is welded to the exhaust, but flanged at the DP. Kinda hard to replace.

I've been hearing good things about this "44K" stuff. My buddy was at SCR Performance yesterday and was hearing good things about that stuff.
 

ktmrider

Well-known member
Joined
Sep 10, 2007
Messages
3,128
Location
Tempe, AZ
I personally like Seafoam but have never used BG44K.
 

toybreaker

iconoclast
Joined
Apr 30, 2006
Messages
3,581
This time of year, the most common contamination found in fuel is water.

I would say throw a bottle or two of "heet" or some such fuel system drier in the tank, and drive it a little.

If it gets happy, you're golden...

If the problems persit, I'd drain the tank, and fuel up the family truckster with the drained fuel. (Dilluted with a full tank, most vehicles won't notice it like a boosted car will.)

As penance, now go to the most expensive station in town, and oversee their board of fare, (I would go with something in a premium, myself /ubbthreads/images/graemlins/wink.gif )

Take a full a five gallon gas can back to the car and see how it likes that.

Changing the fuel filter isn't a bad idea, either, but it should be done after you run a fuel system cleaner (like 44k) thru the system. Any contaminates freed up by the detergent will end up in the filter that's going in the trash rather than the one you are going to be driving on for the next 15k miles.

Good luck, and if you need a logger to look into this a little deeper, let me know.
 
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Thanks Jon!! It's been getting steadily better and is now almost gone as of today. We'll see what tomorrow brings.

On a side note, I think I've developed lifter tick. Not at idle, but at light/medium throttle at any RPM. Sound right?

Just did an oil change under 500 miles ago.
 
Last edited by a moderator:

I was experiencing the same problem, changed fuel filter it was a mess, get real close, i noticed the sound seems to be comming from an injector and it varies from ticking to not ticking, you sure it's not an injector from the bad gas?
 
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