migamb

I just got a 94 RX7, it was idling at 1500 RPM. Today I was doing the initial tune up. Changed oil,trany fluid, plugs and wires. After I started the car and it warmed up it was still at 1500 RPM but now it was bouncing back and forth every second from 1K to 1.5K RPM. When I turned the lights one ot went up to 2K and was rising. When I tapped the gas it would try to go below 1K but then would go back up. It drove fine only when idling or when the clutch is depressed does the problem appear. Any suggestions?

migamb

Any ideas?

JBC

Call MZM performance in Austin. The website is www.mzmperformance.com. Ask for Mohammed, he could tell you what's up.

migamb

I have tried looking everywhere and talkng to different people and can not get an answer. I just got a 94 Touring and it idles at 1.5K RPM. Even when I adjust the flat head screw at the bottom of the TB it does not go up or down. I was getting an engine code for the water temp sensor which can cause these problems according to the manual so I put a new one and the code went away but the problem is not fixed. When I turn the lights on the idle goes up to 2.5K RPM. I tried spraying carb cleaner around the vacuum lines and TB and did not see any change of the idle. I looked through the manual and the closest thing I found to the symptoms I have is a bad ISC sensor, Also in 5th gear it will not go past 3.8K RPM. I did notice the 5th gear synchro needs to be changed since it is crunching every time I shift but I don't think this could be causing this problem. The cars revs fine in 1-3 gears but 4th and 5th it gets to a certain RPM and won't go past that. Any ideas?

Toadman

Hey Migamb, my idle fluctuates as well after the AWS kicks off.
The AWS is the Accelerated Warm-up System that kicks in on a cold start to get your pre-cat heated up quicker. It will boot your RPM up to 2-3k, but when it kicks off(or you manually kick it off by blipping the throttle) the idles drops to about 1k, then starts to fluctuate up and down as the motor heats up. I have no cure for that problem and it doesn't seem to hurt anything, but it is kinda spooky hearing the revving when the car is out front warming up.
RPM is supposed to kick up a hair when lights are on.(Your cooling fans come on at low-speed as well).

migamb

It's not the 3K warm up. After the car is warm and I always tap the accelarator it is stil aroud 1.5K going up and down to 2K when the lights are on. I tried resetting the ECU no help. I am assuming it is a bad valve or a boost leak after the TB since I had the elbow removed and the idle was still high.

ZoomZoom

iTrader: (2)

Try to adjust the IAC. Its the screw on the front of the throttle body. It controls the idle Air control Motor. It meters the air coming in at idle. Your air pump provides secondary air injection and can be controled Via the IAC. Seeing adjusting the idle screw didnt help this should fix the high idle for you. As far as the fluctuating idle. That could be a couple things but not limited to the intake manifold gasket has a small gap in it of if its still the old style paper gaskets it may have blown out a small portion under boost. Also the TPS may be bad. If the IAC Motor is original and has high miles on it that may also be a culprit. This will be a gremlin until you cover all your bases. I suggest taking it to a qualified Rotory specialist. That doesnt include the dealer. they are clueless.