'93 FD studder issue
 

Hey guys, wanted to see if anyone could give me some advice on an issue I'm having with my car. Bone stock '93 RX-7. When driving between 2,500 to 3,000 RPM with my foot lightly on the throttle, just enough to maintain speed, my car will start studdering like it wants to stall out. I can either push in the clutch to resolve the issue or hit the gas. If I hit the gas it lunges forward with more power than I would expect.

One odd detail is that if I drive for a while the check engine light will come on and the suddering issue will disappear. I just pulled the code from the car tonight as 1 long, 7 short according to one site says "sensor output not changed after 25 sec". Not sure what exactly that means though.

Since the issue started I have had it to one shop in California but I'm no longer living close to a rotary shop. We tried replacing the throttle position sensor but that didn't seem to make any difference.

Any thoughts?

There are a few things that come to mind but I'll let the experts chime in. I'm fairly certain there are one or two known rotary shops in NC.

I'd like to invite you to post in the SE Section of the board and ask the opinions of members who live in the Carolina's who is reliable.

replace your o2 sensor

Thanks, I'll give that a shot.

Check and clean all your grounds, bad or dirty grounds can cause the light throttle jerking.

I have the same problem except its on the 1990 turbo II and if when it studders I try to give it gas, even if i floor it, it keeps loosing rpm (kind of like fuel cut off or idk), check engine light barely blimps a couple times but thats when its actually studdering if its not then nothing comes on...