bad fuel pump?
 

So, lately my car has been running pretty good up until this morning.
On my way to a friends house, it started to sputter, almost like a misfire, however it didn't pull any codes. It isn't a bad sputter, just every once in a while. It only does it from about 2000 - 4000 rpms, not in idle or anything.
While I was waiting for her to come out of her house, I was just idling in the parking lot and I heard about 5 knocks coming from the gas tank/exhaust area. It literally sounded like someone knocking on it. I was wondering if the fuel pump would be a likely candidate, or could it just be bad gas or something?
Also, and I don't think this is it, but I have changed the plugs and wires recently, but I didn't get to change one plug yet... just haven't had time. I think this is the original plug and if so, it has 140k miles on it.
One more thing is that I recently had to replace an ignition coil because of a misfire, but that pulled a code, so I don't think that is my problem.
Any help would be apreciated.

140,000 miles on original spark plugs is a lot. I'd be changing those and the wires ASAP. When was the last time the fuel filter was changed? I had a fuel pump go bad on my camaro, but it didn't cause a misfire. It caused the car to run lean at high rpm and the check engine light would come on. If your positive that the knock was coming from the tank I'd be thinking fuel pump as well, but it's odd for the pump to make noises like that.

ur right its odd... i had the same problem it was the plugs, one bad plug can cause that if not then test ur coils, fuel pump swap is a pain in the a** and change ur fuel filter too its cheap but when its dirty it blocks the fuel and makes ur pump bad i had to change it too with the fuel pump... gd luck

As I said, I have changed them all except the one, so that could be it, I'll find out when I can get home to change the last one.
I'm not sure the knock was from the tank, but it was somewhere behind me and was definately on the drivers side :iono:
I have never changed the filter, so I guess I can try that before the whole thing konks out on me.
Something else that I just thought of...
I know I said it idles fine, but I have noticed sometimes where while it is idling it kinda revs between 900 and 1100 and at normal it idles right at 1000. It didn't happened today, so that is why I never thought of it until now.

yea its something eaither with the plugs or the fuel pump so u still have one plug left lol lets hope thats the problem change it and c if not change filter these are all cheap so change them be4 the fuel pump plus the pump is placed in the middle of the tank u said u heared from driver's side...

Don't know what it was, but I drove the car another 25-30 miles today and all was well. Let's hope it doesn't come back up in the future, double time.
Thanks for the help anyways though.

Sounds like a problem my last car had. It would come and go like that too. It started right after I changed the plugs and wires so figured that had to be the problem. Come to find out it was indeed one of the brand new plug wires. It was broke inside and would only connect sometimes.

You should have it scanned, hopefully you or one of your friends has a scan tool that will read live data, even without a code set there maybe a sensor out of range that can cause the problem. I agree the spark plug that you havent changed could be part of the problem, but usually it will miss at all rpm , not just midrange. And a scan will keep you from throwing alot of parts you dont need on it. good luck

figures it would come back.
again, today it did the same thing.
seems to be happening only when i give it more than 1/4-1/2 throttle in midrange
this confuzes me, because once it gets over midrange, it doesnt do it anymore

change your plug. how old are your o2's jw?

no clue, more than likely stock
speaking of that, sometimes i get a tranny code, and once or twice when i have it pulled, it does pull an o2 code
gonna change the plug today, it was raining yesterday

I think you had it @ the beginning - bad fuel pump. Fortunately they will sputter on for quite awhile before quitting completely, unfortunately it means a new gas tank...

When it comes to fuel pumps use a pressure gauge. They are not expensive to get just screw it on and turn the key on then check. Lot of FP's get tossed when it's another problem.

As others have said it's either ignition system or could be a vac leak. Vac leaks in the intake mess up the fuel air mix and cause rough and stumble idle or eventual stall.

Last month my truck had no power, if you pushed the gas pedal down the rpm would rev like you threw it in neutral. I thought the trans was shot but turns out it was the fuel filter. Truck has 150,000 on it the fuel pump has been whining since day one but my neighbors truck same year doesn't. Anybody have that whining sound from the fuelpump ? I know it's $$$.$$