Stuttering While At Speed

[GalacticPonage]

Recently I've been having a problem where when it's a cold wet day the car stutters about 100 rpm when I'm driving at a constant speed. It makes kind of a bang and it's only when I keep the car at a constant speed for more than a couple seconds. I'm positive it's something to do with the trans and I think it might be the torque converter trying to lock up. Is there a way to test the solenoid for the torque converter clutch without dropping the pan or are there other things that could cause these symptoms. Thanks in advance!

 

[mikestang63]

check your line pressure and TV cable

 

[Noobz347]

Recently I've been having a problem where when it's a cold wet day the car stutters about 100 rpm when I'm driving at a constant speed.

Wait until it gets dark. Run the car at idle with the hood open and check for arching around your plugs and wires.

 

[GalacticPonage]

Well I did think it was the trans but I went through the ignition system and there was quite a bit of oxidation in the cap/rotor. It probably needs a tune up but for now i cleaned up all the crud with some scotch brite and that helped enough so the stuttering doesnt happen nearly as often. Ill update if it fixes the problem after I do the tune up

 

[General karthief]

What is a galacticponage?
What can I say, I'm a boob, an old boob at that.

 

[GalacticPonage]

So I'm going to open this up again. Since last time I've taken the trans out to put some heavy duty bands, clutches, solenoids, etc and a shift kit. I've also done a full tune up (cap, rotor, wires, plugs) and the problem still persists. Here's a video of exactly what it's doing.

View: https://youtu.be/JeDWO7jyExI

If anybody can think of what it could be that would be great this thing is driving me nuts

 

[GalacticPonage]

Forgot to mention that the car has a few vacuum leaks but even when I capped them off it still does it. Unless there's something that needs vacuum that's not getting it anymore that's causing it but I'm not sure what half the lines go to. The one going to the regulator is fine though

 

[Noobz347]

 

[Mustang5L5]

Is engine speed actually changing or is the tach just jumping around?

It's a pretty damn quick jump to mAke under load. My car doesn't even blip that fast in nuetral

 

[General karthief]

I couldn't tell but does the engine miss when the tach jumps?

 

[GalacticPonage]

Is engine speed actually changing or is the tach just jumping around?

It's a pretty damn quick jump to mAke under load. My car doesn't even blip that fast in nuetral

When the revs drop for that split second It feels like something is slowing the car down. The same feeling you would get if you jabbed the brakes real quick

 

[GalacticPonage]

I couldn't tell but does the engine miss when the tach jumps?

I can't hear or see a miss. Even if it was I don't know if you'd feel it slow the car down like it does and like I said the car just had a tune up and new injectors were put in almost two years ago so I wouldn't know what would cause it

 

[General karthief]

Coil jump'm to ground?
Check your connections, coil and all grounds

 

[GalacticPonage]

I double checked all my grounds and made sure they were tight and making good connection and I also redid half the vacuum system and there are no leaks as far as I can tell. It still does it and I'm at the point where I'm considering just throwing an LS in it. I know. It's that bad. It really only does it when the outside air temp is cold and the engine is cold. If the air outside is warm (>60F) it's perfectly fine when I start it cold which doesn't make any sense to me

 

[jrichker]

Dave you dumped the codes? You may have an engine problem that hasn't been diagnosed.

Dump codes sticky

Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. Codes may be present even if the CEL (Check Engine Light) isn’t on. You don’t need a code reader or scanner – all you need is a paper clip, or if your lady friend has a hair pin, that will do the job.
I highly suggest that you read it and follow the instructions to dump the codes. http://www.stangnet.com/mustang-forums/threads/how-to-pull-codes-from-eec4.889006/