Rogue_Wulff

Today I finally got to drive my 83 for the first time, and I took it out, even though it was cool and rainy. I bought the car just over a month ago, but had to wait on some paperwork to title it.
While the car runs great, and drives ok from what I could tell on wet crappy roads with 205/50-15 tires.
I have a (silly?) question. While slowing down in gear, about 2500 RPM or so, the car starts lunging back and forth like a engine with a healthy cam will do. Gives you a good jerk back and forth, and the slack in the driveline slaps back and forth. Other than sounding like it runs very rough only when totally off the throttle, I cannot tell that it has any other issues.
Any ideas what would be causing this? I will be honest, today is the first time I ever drove any rotary powered car, so if this is "normal", and I look like a total newbie, well, I am. At least to rotaries.
As far as I know, the 12A is totally stock, and still has the Nikki carb on it, but the exhaust has been modified. Straight pipe to a Power Tech (ricer) SS muffler, no converters.
Pics will come soon, if anyone is interested.

82streetracer

iTrader: (1)

sounds like a shutter valve problem.

its a valve that cuts off the rear rotor under decel or someithing like that.

If you look on the engine side of the intake manifold, you will see a vacuum motor connected to a bracket.

remove the motor and wire the shutter in the open position.

note, with the engine off, it will be in the open position.

Rogue_Wulff

Thanks, will check that. I have seen info about the shutter valve, and have a vague idea how it works.

cpt_gloval

iTrader: (1)

i just disabled mine and was pretty happy with it.

H4Inf

Hmm, I never had one, but now I know why my car acts like this ;-)

Aviator 902S

Are you sure this happened at 2500 rpm? Usually the car jerks like that if you slow down in too high a high gear to below say, 1700 or 1800 rpm. The problem should go away when you depress the clutch, or if you downshift into a gear that will bring the revs back up. If this cures the problem everything is normal.

Rogue_Wulff

Perhaps I was slightly mistaken about the RPM. I guess I am just too used too the way my nissan truck runs.
I must have discovered a "normal" behaviour with these. I told ya, it was my first ever time in a rotary powered vehicle.
Today was a little nicer weather, so I took it out again. Drives much better with the tires fully aired up I guess they tend to lose a little air when left sitting for a year.........

H4Inf

Nice :-) Yeah if it starts to get jumpy usually drop a gear or give it some more power. Always ready on the clutch hehe