94 Gt Sputter Issue

[Hunter Pannell]

Hello. So I have recently bought this stang and there is a situation going on with it. I've owned it for 2 weeks now and CAN NOT figure out why this thing is sputtering!

Let me explain:
1st gear to 2nd does fine. No problems
2nd gear to 3rd there is a hesitation of a "sputter" before going into 3rd.
3rd to 4th really no issue.
4th to 5th """
Now 5th gear any speed it's the worst! If I'm cruising down the highway going 65. It's like its misfiring in a way. But it's way more of a sputter, and it's not just a one time deal. If I hold the gas down at 65 it will continually do it.

I have changed the ignition coil, cleaned MAF sensor and plug that goes into the harness, checked plugs for gas, wires are fine too.

I have researched all forums I can find but there have been no solution replies or they are having a rough idle which I don't.

The car idles great no hesitation or miss. It's only doing it while driving. Any information will greatly be appreciated!

 

[General karthief]

Run the codes,
https://www.stangnet.com/mustang-fo...codes-from-eec4-in-86-95-5-0-mustangs.889006/
This thread will show you how, post the codes
Any modifications?

 

[Hunter Pannell]

Run the codes,
https://www.stangnet.com/mustang-fo...codes-from-eec4-in-86-95-5-0-mustangs.889006/
This thread will show you how, post the codes
Any modifications?

No mods. Bone stock. Still has smog pump as well.
*edit: I will have to get codes tomorrow. But thanks for that link.

 

[General karthief]

Bone stock has advantages, you don't have to figuare out/fix botched junk.

 

[Hunter Pannell]

Yeah it definitely does. It does have flomaster exhaust that I know of. But that's the only mods I know about

 

[Hunter Pannell]

Update

Have not yet gotten a scanner. Will probably be Friday until I can.

 

[jozsefsz]

Checking codes is good. I'd also check fuel pressure and timing - those won't directly show up us codes but both can cause sputtering at high load.

 

[Hunter Pannell]

Ok thanks. I've heard to check my timing, but what are you considering a high load?

 

[General karthief]

Accelerating from low rpms like being in 4th gear at 35 mph going up hill or speeding up from 55mph in 5th.

 

[Hunter Pannell]

If I have the gas I would say 1/4 to 1/2 throttle to what your saying it will. But if the pedal is fully engaged it won't do it.

 

[Hunter Pannell]

I have also done a quick test on the MAF sensor. While engine running at normal temp, I unplugged the sensor and the motor did not hesitate it stayed running. Thoughts??

I've heard that means the MAF sensor is bad but am not sure with these late model mustangs.

Also to add to timing: I have noticed that my idle rpm is 1k. I feel it should be lower than that. Not to mention when I have the clutch engaged the rpms will rise from 1800-2500 I'm not sure if that's part of an issue I'm dealing with at the moment but that is rather aggravating as well.

 

[General karthief]

Can't tell you anything for sure until you check for codes, your just guessing. Don't chase your tail, one thing at atime.

 

[Hunter Pannell]

Can't tell you anything for sure until you check for codes, your just guessing. Don't chase your tail, one thing at atime.

Oh I know. I've seen it done thousands of times through forums I have read. I'm gonna try to get me a scanner and I'll get back with y'all after that

 

[Hunter Pannell]

Update

I got my hands on a code scanner that displays the 3 digit codes. I ran the KOEO test came back for a FPR malfunction. So I changed that out. For some reason the scanner won't allow me to do KOER test so I can't get the full codes. Idk if it's because I don't have the clutch in or what but I'm going to mess with it some more this week. However, the fpr made a huge improvement but the problem still exist. That was the only code worth mentioning, other codes were having to do with transmission temp and bad shifting solenoid that I already knew about

 

[95gt1985]

Update

I got my hands on a code scanner that displays the 3 digit codes. I ran the KOEO test came back for a FPR malfunction. So I changed that out. For some reason the scanner won't allow me to do KOER test so I can't get the full codes. Idk if it's because I don't have the clutch in or what but I'm going to mess with it some more this week. However, the fpr made a huge improvement but the problem still exist. That was the only code worth mentioning, other codes were having to do with transmission temp and bad shifting solenoid that I already knew about

What was the fix to the issue?