Unusual problem

[Chuckieduck]

Took my 96 Cobra out for a ride today and got it up on the interstate. I have been noticing a problem with it in 3rd and 4th gears when I get to the speed I want to run at it feels like the car is surging. Got it up to running a steady 70 today and you could feel the car surging a little. It's not very noticable but I can feel it's there. If I put the cruise on you can feel it a little more like the cruise oiver compentsates. Like your doing a steady speed and it surges just a bit and it slows back down until it hits the right speed then surges again. You can watch the tach and you can't see any changes. The car runs perfect other than that. I know the IMRC plates are not working since my drivers side cable is broken. The only MOD to the car is 4:10 gears.

Any suggestions on what it could be?

 

[Mustang Matt]

I'd wire both IMRCs wide open and see if it changes. The car is going to do strange things with one shut and one open.

 

[Chuckieduck]

The one that has the broken cable is shut all the time. I got my hand behine the head and can open it and feel the spring pull it back closed. Same thing on the other side but the cable isn't broken which I'm sure would act kinda funny when the plate opens and 4 cylinders are getting more air than the others. But the speeds I'm running are all below 3K RPMs, so I don't think that would be causing my problem.

 

[tonewyork89]

i mean this could be a number of issues, obviously below 3000rpms the imrc aren't the issue, could be an ignition issue, maybe you need new coils/wires/plugs? i would hope it's something simple like that