sputtering while accelerating

legalize420

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
#1
i noticed this started happening about a week ago. i thought maybe it was bad gas but i filled up again and its still there. i pulled the codes today and came up with 565, 314, and 311. i did a search and others suggested that 314 and 311 will come up if you deleted smog. the cannister purge is part of the a/c system right? so the codes do not seem to reflect this issue. the plugs and wires were replaced not to long ago. dizzy, fuel pump and filter were also replaced within the past year. i checked the timing its good. cleand the maf. the car drives and idles fine. it just makes a sputtering noise and slight hesitation when you give it gas and it seems to clear up once it gets to about 2500 rpms. what else could it be? i was thinnking oxygen sensors but wouldnt they show up in a code? any suggestions on what else to check?
 

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#2
I had this problem as well for as long as I can remember. I replaced the wires last spring and it seemed to cure it for a good while but now its just as bad as it was before. I've got a feeling its the MAF but I can't be sure. Its really bugging me. I wouldn't doubt my EL headers have burnt-through the #3 and #4 wires already, so I'll be swapping to UL headers and Livewires soon to see if that cures it.

I check for codes every now and again and there are never any stored codes. The one you have for the canister purge is actually the evap system canister purge solenoid. I don't believe that would cause any issues like you are experiencing, but if the line coming from the manifold side of the solenoid is disconnected or leaking, then you have a vacuum leak.
 
#7
It sounds to me like a very mild misfire. Not sure what code 565 is, my Chilton manual doesn't give 3 digits, only 2.

What brand were the plugs & wires? I have heard that these engines (94-95) only like factory stuff.

Unless the O2 sensors are complete junk, I would doubt they would cause a driveability issue like you describe.

I would have to lean toward plugs and wires more than a fuel issue, especially if it goes away as the RPMs get higher. With all the distributor-equipped engines I have owned, a misfire and bad plugs and wires always start off as a little hesitation and then get worse and worse. Most of the cars that I have seen with a bad fuel system/pump are a crank-no start issue, not a performance issue through the RPM range. Not to say that it can't happen.

Good luck.

Keep us posted.
 
#8
ford wires and autolite 103's. one o2 sensor was replaced since i had the car the other one i do not know. if they were a problem wouldnt there be a code? it does not necessarily go away but it does not seem as bad in the higher rpms. if im just crusing its fine but when accelterating from a stop or while moving its kinda slugish and makes a low tone sputtering sound from the exhaust. i only pulled one plug earlier. im going to change the plugs tomorrow since there inexpensive.
 
#9
Absolutely, it sounds like a bad plug (or several) if it minimizes at higher RPMS more than lower ones. Typically, I found bad plugs seem worse "around" shift points, give or take a few hundred RPMS. When the engine is at idle, the spark is so infrequent that it doesn't seem that evident, but under a slight load, it seems worse and under a REALLY heavy load (high RPMS) it isn't THAT bad.

Make sure you save the OLD plugs IN THEIR SPECIFIC ORDER because there could be an issue with a particular if one is fouling prematurely. But it could just be garbage plugs. I like to think of plugs as a tell-tale sign as to what is going on in the engine, I scrutinize them no matter what kind of engine I yank them from.

In my experience with GM computers, they store misfires no matter how slight they are, so there should be a chronic trail of misfires if there is a real issue.

But if you are going to commit to replacing the plugs tomorrow, at least it would rule out bad plugs.

Good luck, keep us posted! ! ! ! !
 
#13
legalize420 said:
i noticed this started happening about a week ago. i thought maybe it was bad gas but i filled up again and its still there. i pulled the codes today and came up with 565, 314, and 311. i did a search and others suggested that 314 and 311 will come up if you deleted smog. the cannister purge is part of the a/c system right? so the codes do not seem to reflect this issue. the plugs and wires were replaced not to long ago. dizzy, fuel pump and filter were also replaced within the past year. i checked the timing its good. cleand the maf. the car drives and idles fine. it just makes a sputtering noise and slight hesitation when you give it gas and it seems to clear up once it gets to about 2500 rpms. what else could it be? i was thinnking oxygen sensors but wouldnt they show up in a code? any suggestions on what else to check?
Click to expand...

Is the hesitation in part throttle acceleration or wide open throttle acceleration? Motor cold, hot or both?

Part throttle acceleration is related to the actual engine (fuel/spark/air), EGR or O2 sensors.

WOT acceleration is related to the actual engine or the maf/ect/iat.

I would rule out the engine and check all 8 plugs/wires/cap/rotor. Then do a cylinder balance test. Then clean your maf/iat sensors.

Let me know whether it's part or WOT accel we are talking about to further diagnose this.
Scott
 
#14
part throttle and WOT is when it happens. if im just crusing its fine. only when accelerating. if i slighly press the throttle it is not as bad and might only sputter once or twice. if i give it 3/4 throtle to WOT is when it happens. also when accelerating from a stop it does it more in the lower rpms then starts to clear up but not neccesarly go away until i get to crusing speed.
 
#18
Well this may not help but i had a similar problem in my Jeep a while back, when i applied a heavy amounts of acceleration it would sputter. I too thought it was a spark plug or vaccum leak. Took it into the shop and found out the Fuel Pump was going bad. So might want to check that could be a possibility.:shrug:
 
#19
thanks everyone for the replys. i just got done changing the plugs and i found the problem. #8 plug wire has a nice gash in it. i still have my old wires in the garge so i will dig them out in the morning and throw them on and hopefully i should be good to go. im pretty sure they are in good shape and i only upgraded to change the color. worse case senario if one of the old ones has a burn in it will i be ok driving around for a day or two with seven 8mm wires and one 9mm or vice versa?
 
#20
Shouldn't be a problem. Pretty much the same amount of voltage will get to the plugs with either wire. I ran a different wire on my #3 plug for about 2 months because I had pulled that one off and it came apart. No issues. Only bothered me ALOT because I had 2 different color wires :nonono:
 
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