do I have bad gas or what? real mechanical Q
 

OK, sorry for the leading topic, here's the deal,

tonight while driving home, I got the car up to normal operating temp, shifting at 3k through all gears, modest acceleration. After she was up to temp (between the first and second marks), I started getting on it a bit, I was ok taking the shift points to 4.5 on a modest acceleratio curve, not problem.

BUt, when I tried going strong up the rpms btwn 2nd and 3rd, at about 3500rpm I got this bad rattle sound from the engine. I backed off and listened for other sounds . .. nothing (except my heart and wallet beating). Everything seems normal - oil pressure, temp and oil level (mine actually tracks pretty accurately). There seems to be no problem as long as I kept it easy on the way up.

THe only variable that I can think of is that about 30 miles ago I filled up the tank - it was really low and I couldn't wait to ge to AMOCO, where I ALWAYS fill up. I filled up with Sunoco.

Ok, all that for the question: is it possible that it is the diferent gas? Is it b/c I might have pulled some sludge from the bottom of the tank? Or, do I have a real mechanincal problem here? btw fuel filet was changed about 20K miles ago.

Thanks in advance

Adam

For the minimal cost, I'd change out the fuel filter. You say there's 20,000 miles on it? Keep the gas that's retained in the fuel filter and dump it into a glass jar, let it settle and have a look at it to see if any water has settled to the bottom of it. That should be a pretty good indicator if you have water in your gas.
Regards,
Gary

Gary - I am planning on replacing the fuel filter, but do you think that might be the sudden cause of the rattle?

Adam

Anybody else have any thoughts? Is it possible that it was just the change in gas, or maybe sludge from the bottom of a near empty tank that caused this rattle or do I have something serious to worry about?

thanks

Adam

Probably not the case on your car, but the bypass pipe I put in required I screw something in the O2 sensor (not needed on my '78). The tapered brass fill plug I used in that sensor rattled something awful before I figured it out.

You might go over your exhaust system though. Nuts, bolts, straps.

John