ok. 1) new alternator but dash dims when i hit the brake. need beefier alt? 2) lowest idle i could get was ~1200rpm but engine shakes like a beast. any suggestions?

 

Where does the shaking seem to come from, and does it shake teh whole car? What mods have you done or maintenance issues?

 

well just the intercooler area shakes...i dont really want to throw it away =/

 

oh yea i forgot to mention the oil gauge and boost gauge doesnt work either ;__;

 

Hmmm I would check teh mounts first then start on the mechanicals, but Im not a TII expert either so the intercooler shake is new to me

 

I just noticed today my car shakes like mad and i'm idling at 650. Can low idle cause my whole car to shake? Maybe motor mounts ar bad?

 

That is low, idle should be around 800-900 depending on conditions. Bad mounts can cause the car to shake, loose exhaust can cause it, and a big one, if you have ever had to mess with the front E-shaft bolt, you may have let something slip out of palce in teh front stack, causign balance issues(speakign form experience here as my front counterbalance was completely off teh key.)

 

i just got my car too =/

 

Check the timing

 

Well congrats and welcome to the wonderful world of Rotary Ownership. If I were you right now, I would begin some reading in the FAQ and also make a post or two in the west forum here, that way you can see if anyone is local to yourself for a better and more accurate assumption of what can and possibly is wrong.

 

What brand, 'type' or AMP spec was the alternator that you purchased?

I believe the AMP rating on a s4 N/A is like 70A, the turbo's spec is like 80A--but people swear by the 3rd gen alternator which can net upwards of 120A. I might be confusing numbers (s4-s5 and N/A-TII) but the point is that there are several different specs in Rx7 alternator amperage.

Perhaps you got an alternator that is putting out a 'lower than desirable' amperage?

I would really check your TPS (throttle positioning sensor) for the inability to lower the idle and the 'lowest idle' shaking. A bad or out-of-spec TPS can cause all types of erratic idling/drivablilty issues. This might be coupled with a broken motor-mount or something of the sort.

 

im a newb so can you tell me where the TPS is?

 

Man, you'd really have to see a picture... Try searching, or maybe someone will be nice enough to find/take a pic for you.

Search for 'TPS adjustment' or maybe just 'TPS'. Perhaps you'll stumble upon a pic/write-up that will help you out.

 

Turbo model: http://fc3spro.com/TECH/HOWTO/TPS/tps.html
NA: http://www.racingrotary.com/tps.htm

Your TPS may look a little different but they should be in the same location.

 

you guys are awesome ill try this when there is more light out. i think i found out why my stock boost gauge isnt working (i saw a sensor in the turbo insulator area that is seperated from the wire; seperated as in cut.) I still dont noe about the oil pressure gauge though =/

 

If the oil pressure gauge isn't working it might be due to a bad oil-puessure sensor (they are known for failing) or some fault in the wiring... The electrical wire/'clip' connection setup on the pressure sensor is also is known for getting seriously gunked up since it is almost directly below the oil-filter pedestal.

You might want to clean that connection up and see if it works.

The oil-pressure sensor is a brass, mushroom shaped thingy coming perpindicular(sp?) out of the rear-iron, above the heater-hose nipple and below the oil-filter pedestal. It has a small wire running to the 'tip' of the mushroom where it's 'clipped' into place. If you're having trouble visualizing or finding this part, download the 'oil system' part of the FSM and check out where the pressure-sensor is located. There are links to the FSM at the top of the 2nd gen. tech. main-page in the FAQ area.

 

BTW, an aftermarket boost-gauge should be one of your very first mods.

 

If you just got the car I would check everything. Starting with new fluids, Change spark plugs and wires (if needed) Make sure the leading and trailing plugs are right, Check the tps (as mentioned) check for any vac and intake leaks.

 

Thanx eriksseven, FirstRotaryExp, and Sgt. Pepper. the TPS thingy helped a lot you guys are awesome. ill try to get a boost gauge but im kinda low on $$$ just bought the car =/. if i have anymore problems i hope everyone here helps me