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I'm having some weird issues.
Driving about normally, changing gears normally, clutch engages like normal. However, coming up to lights, when I depress the clutch, the revs would drop to 500-200RPM. until i plock it back in N then get off the clutch. It will then gradually pick up the revs again.

Any hints???

Have you checked your base idle speed?

There is also a neutral switch on the gearbox that I've heard can sometimes cause idling issues.

How do you check it? Normally the idle speed sits abit below 1k. But how do I get an exact figure?

I should also mention this doesnt do it all the time. Usually crops up after a long drive and i restart the car again...or even DURING the long drive.

Easy! You need an automotive multimeter that reads rpm to get a precise reading. Use a bent paperclip to short the TEN and GRD terminals to enter the test mode. Connect the multimeter red lead to the IG terminal and black lead to GRD on the diagnosis connector and read rpm. Adjust idle speed to 850rpm via the Phillips head screw on the throttle body.

you definitely have something that isnt quite right.

Im far from an expert but I believe there are a couple of switches that can affect idle. If Im right, one takes its reading from the clutch pedal. Maybe that has failed, loose/broken wire etc. It sounds related directly to the clutch pedal. Clutch in, poor idle. Clutch out and car in neutral, all is fine. Sounds to me like your base idle is probably fine but some sensor is sending incorrect data altering the idle speed.

I've got that feeling as well Bauer, otherwise my idle would be effected regardless of situation I would assume.

AFAIK, its only affected from coasting to stop. Once its stopped, the idle remains pretty static no matter how many times i press the clutch, I THINK, i'll investigate it abit more tomorrow on the way to work.

Have you recently disconnected power (battery) for a few minutes or more? This dumps the ECU memory and can a long time for the system to catch up if the base idle speed is wrong.

No I haven't. Not recently.

Been doing abit of driving. Driving 30odd kays to work everything was smooth, idle was as still as a baby sleeping. Holding very well.

On the way home, stuck traffic, still idling perfectly, then suddenly the idle drops down to about 200-300RPM. Then goes back up to 800-850rpm. Then for about the next 3 minutes, the same clutch-in problem appears then disappears again.

The NA6 has a switch on the clutch pedal. There is also the neutral switch on the gearbox. The combination of these two switches effects the engine idle. The clutch switch broke on my car. From memory it caused very high idle when the car was in gear, and the clutch was disengaged.

J.

hmm, mine sounds like the opposite...So the switch is working overtime?

I've done abit more driving to narrow the problem. Its got nothing to do with the clutch. It happens when i plonk it into neutral. Regardless of speed, I did a test where I was slowing down to the lights, threw it in neutral and the revs drop. I tried while moving a slow speeds, WITHOUT USING THE CLUTCH, and the same thing happens. Its when i throw it into neutral is when it happens. Though usually only at night...

I had the same issue on my NA6. Do as Guran suggest and get the idle setup so at least you know where you are starting from. In my case that was all that was needed.

Its when i throw it into neutral is when it happens

When you put it into neutral the engine switches to the idle circuit, no matter what the road speed. If the base idle speed is to low then the engine will behave as you describe. Set the base idle speed first and if that doesn't help then start looking for other problems. It's free and easy to do.

Sounds great! Does anyone have an automotive multimeter around St George area???

You don't need one - use the car tacho.

sounds like it could also be the 'idle dip' problem:
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