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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

sputtering while accelerating

  • Thread starter Thread starter legalize420
  • Start date Start date Jan 28, 2007
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legalize420

Active Member
May 21, 2005
1,541
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South Florida
Jan 28, 2007
#1
  • Jan 28, 2007
  • #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?
 

1TallMF

New Member
Apr 17, 2006
955
1
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Montreal
Jan 28, 2007
#2
  • Jan 28, 2007
  • #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.
 

legalize420

Active Member
May 21, 2005
1,541
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37
South Florida
Jan 28, 2007
#3
  • Jan 28, 2007
  • #3
i have the wires away from the headers and i did not see any burn marks when i inspected them so im assuming they are good. does this sound like a fuel problem or spark?
 
B

bigap15

New Member
Apr 9, 2005
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Jan 28, 2007
#4
  • Jan 28, 2007
  • #4
i had the same problem, but mine caused a horrible idle too. Tps fixed the problem on mine.
 

DDSTANG94

New Member
Dec 9, 2006
465
2
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FRASER, MICHIGAN
Jan 28, 2007
#5
  • Jan 28, 2007
  • #5
check the timing?
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Jan 28, 2007
#6
  • Jan 28, 2007
  • #6
tps and iac are a little over a year old. timing is fine. i had it at 10 and thats where it was when i checked it.
 

Bens95cobra8594

New Member
Sep 18, 2006
49
0
0
The Empire State
Jan 28, 2007
#7
  • Jan 28, 2007
  • #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.
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Jan 28, 2007
#8
  • Jan 28, 2007
  • #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.
 

Bens95cobra8594

New Member
Sep 18, 2006
49
0
0
The Empire State
Jan 28, 2007
#9
  • Jan 28, 2007
  • #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! ! ! ! !
 

Bens95cobra8594

New Member
Sep 18, 2006
49
0
0
The Empire State
Jan 28, 2007
#10
  • Jan 28, 2007
  • #10
If you can, yank the plugs tonight and see if any of them have carbon tracking on them. If yes, you know which one to replace. But all at once would probably be a good idea if one (or a few) are bad.

Good luck!
 

DDSTANG94

New Member
Dec 9, 2006
465
2
0
FRASER, MICHIGAN
Jan 28, 2007
#11
  • Jan 28, 2007
  • #11
My experience was th opposite, I had more problems at upper rpms when my car needed a tune up
 

SQUEEZE&STROKE

New Member
Jun 24, 2005
0
0
0
SOUTHERN CA
Jan 28, 2007
#12
  • Jan 28, 2007
  • #12
Check for vacuum leaks...if thats all good check the gaps on your plugs...my Lightning had the same problems for about a week, turned out the plug gap was too wide. After I regapped the plugs...everything was good again.
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Jan 29, 2007
#13
  • Jan 29, 2007
  • #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
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Jan 29, 2007
#14
  • Jan 29, 2007
  • #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.
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Jan 29, 2007
#15
  • Jan 29, 2007
  • #15
btw, i just picked up the plugs so im going to change them either tonight or in the morning. i will give the wires a closer look and do the cylinder balance test.
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Jan 29, 2007
#16
  • Jan 29, 2007
  • #16
double post
 

1TallMF

New Member
Apr 17, 2006
955
1
0
Montreal
Jan 29, 2007
#17
  • Jan 29, 2007
  • #17
Cool man, keep us posted. I have the exact same symptoms as you are experiencing and would love to fix it.
 
Reactions: Thebrokenstang

qballenko

New Member
Dec 6, 2006
0
0
0
Jan 29, 2007
#18
  • Jan 29, 2007
  • #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.
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Jan 29, 2007
#19
  • Jan 29, 2007
  • #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?
 

1TallMF

New Member
Apr 17, 2006
955
1
0
Montreal
Jan 30, 2007
#20
  • Jan 30, 2007
  • #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
 
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